区块链图解高清,区块链 图解

区块链是一个可以用于记录数字资产的分布式数据库，它是一个去中心化的账本，可以在网络中安全地存储和记录信息，使用者可以通过某种方式来验证这些信息。它的最大特点是构建一个开放的、可信任的网络，能够让参与者之间安全地进行交易。

第一个关键词是去中心化，去中心化是指分散的管理和控制权，没有一个中心化的机构或者组织拥有全部的控制权。去中心化的系统有助于保护数据的安全性和一致性，它可以让每个参与者都有机会参与到交易中来，并且可以确保交易的安全性。去中心化可以减少管理成本，提高效率，同时也可以提高系统的安全性。

第二个关键词是可信任的网络，可信任的网络是指一个可以让用户相互之间可以信任的网络。可信任的网络可以使用区块链技术来实现，它可以通过共识机制来确保数据的安全性。可信任的网络还可以实现去中心化的管理，可以让每个参与者都可以参与到交易中来，更安全地实现数据交换和传输。

最后一个关键词是分布式数据库，分布式数据库是指将数据分布在多个节点上，可以实现大规模的数据存储和处理。分布式数据库可以提高系统的可用性和安全性，因为它可以把数据分布在多个节点上，使得数据更容易被存储和处理。分布式数据库可以支持多种数据类型，包括文本、图像和视频，可以更好地满足多种数据存储需求。

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① Blockchain 100 Questions: What information is recorded in the blockchain?

The blockchain is the big ledger of the Bitcoin network, and each block is equivalent to an item in the ledger. One page. So what information is recorded in the "account book

"? Currently, each block of Bitcoin mainly records data such as block header, transaction details, transaction counter, and block size.

The "block header" contains all information except transaction information, mainly including the hash value of the previous block header:

Used to ensure that blocks are concatenated in order ; Timestamp: records the generation time of the block; random number: the answer to the arithmetic problem of the entire network mine

; Difficulty target: the difficulty coefficient score of the arithmetic problem.

"Transaction Details" records in detail the transferor, incomer, amount and digital signature of the transferor

of each transaction, which is the name of each transaction in each block. main content.

The "transaction counter" represents the number of transactions contained in each block.

"Block size" indicates the size of each block data. Currently, each block is limited to 1MB, and the possibility of expansion in the future cannot be ruled out

.

② One article to understand the Internet blockchain

One article to understand the Internet blockchain

One article to understand the Internet blockchain. To understand the blockchain, We have to study the brief history of blockchain technology development starting from the birth of the Internet, discover the motivations for blockchain, and infer the future of blockchain. Let’s understand the Internet blockchain in one article.

Understand the Internet blockchain in one article 1

The originator of blockchain is mahjong, and the earliest blockchain was invented by the Chinese! The blockchain is just like Mahjong, except that Mahjong has fewer blocks. Mahjong only has 136 blocks. The rules of Mahjong vary from place to place and can be regarded as a hard fork of Bitcoin.

As the oldest blockchain project, Mahjong has a team of four miners. The first one to dig out the 13 correct hash values ​​will get the accounting rights and rewards. It adopts the method of being willing to admit defeat and not cheating. Thousands of consensus mechanisms!

Mahjong is decentralized, everyone can be the banker, and it is completely peer-to-peer.

Mining pool = commission from the boss of the chess and card room.

It cannot be tampered with, because convincing the other three people requires too much computing power and physical strength.

A typical value Internet. The value in my pocket didn't last eight rounds before it went into their pockets.

Chinese people are basically good at playing mahjong. In terms of blockchain, they produce 70% to 80% of the world’s mining machines and have the most computing power in the world, aboutAccounting for 77% of the computing power

Mahjong is actually the earliest blockchain project:

1. A group of four miners first collides to produce the correct hash value of 13 numbers. Miners can obtain accounting rights and receive rewards.

2. It cannot be tampered with. Because convincing the other three people requires too much computing power and physical strength.

3. Typical value Internet. The valuable digital currency www.gendan5.com/digitalcurrency/btc.html in my pocket ran into their pockets after eight rounds.

4. Decentralization, everyone can be a banker, it is completely peer-to-peer.

5. UTXO, unspent transaction expenses.

There is another blockchain method of credit, assuming that everyone has no cash

Let’s take a closer look. When everyone reaches a consensus, we see There is no intermediary or third party to judge C’s win, and the rewards given to C do not need to be transferred to C through a third party. They are all direct peer-to-peer transactions. This process is decentralized, and players (miners) record their own records. After recording the results of the first game, B Dahu drew thirteen pieces, and B drew Jia Dongfeng. After the record is completed, a complete block is generated, but remember, this is only the first game. In the entire blockchain , this is just one node. After the 8 rounds mentioned at the beginning, there are 8 nodes (blocks). The 8 blocks are connected together to form a complete ledger, which is the blockchain. Because everyone has one of this ledger, it is a distributed ledger. The purpose is to prevent someone from tampering with the record. At the end of the game, it is clear who wins and who loses.

Four men (A, B, C, and D) got together to play mahjong for money. None of them brought any cash, so they asked a beautiful woman (centralized) to keep a book and record who won how much money in each round. , Who lost how much? At the end of the day, everyone uses Alipay or WeChat to pay and settle the ledger. However, if this beauty made a mistake in accounting or was bribed by one of the four people in advance to make a mistake on purpose, there is no guarantee that the outcome of this game will be fair, just, and reasonable. ,dont you agree? then what should we do? If you "play mahjong", you can use "blockchain" as the game rules and adapt it as follows:

Four men (A, B, C and D) got together to play mahjong for money. No one brought any cash. B said Let the beauty she brought keep accounts. A said that none of us knew this beauty, so the four of them, A, B, C, and D, agreed that everyone would keep accounts at the same time (decentralized) on their mobile phones (blockchain nodes) for each game. ), after finally playing mahjong and paying with electronic money directly on the mobile phone, everyone checked the accounting results. The accounting results should have been the same.

Assume that the original result is the account recorded on A’s mobile phone: B owes A 10 yuan. But the record on B's mobile phone shows that there is no debt, but the other two people (C and D) have the same accounting as A, so the settlement is still based on the majority rule. In addition, everyone has a different understanding of the situation.The impression of B's ​​integrity is bad, so he won't take B with him next time he plays mahjong.

Unless B bribes two people (C and D) in advance to deliberately cheat, but the cost of B bribes them is 100,000 yuan (10,000 times the default of 10 yuan), then in common sense, B only You can choose to give up because the cost of counterfeiting is too high.

Assume that even if B is secretly willing to pay a high price of 100,000 yuan to buy C and D to do this silly cat transaction with huge losses during the card game, the rules of the blockchain are to keep accounts based on timestamps. Yes, it turns out that B owed A 10 yuan when debiting the account at 1 p.m., that is, when C and D changed the account at 3 p.m., time is irreversible and they can only record 3 p.m., which does not comply with the rules of the game. .

In fact, in 2017 the blogger has developed a set of Mahjong coins

China’s earliest blockchain project: a group of four miners, first starting from 148 random numbers The miner who collides with the correct hash value of 14 numbers can obtain an accounting right incentive. Since distributed accounting requires the consensus of several other miners, each accounting transaction takes about ten minutes.

Understanding the Internet Blockchain in One Article 2

1. Before the birth of Bitcoin, 5 Internet technologies that will have a significant impact on the future of the blockchain

In 1969, the Internet was born in the United States. Since then, the Internet has expanded from four research institutions in the United States to the entire planet. In terms of application, it has expanded from the earliest military and scientific research to all aspects of human life. In the nearly 50 years since the birth of the Internet, five technologies have been of particularly great significance to the future development of blockchain.

1. The TCP/IP protocol born in 1974: determines the position of blockchain in the Internet technology ecosystem

In 1974, the most critical step in the development of the Internet was taken by The TCP/IP protocol, the core communication technology of the Internet jointly developed by American scientists Vinton Cerf and Robert Kahn, was officially launched.

This protocol enables the transmission of information between different computers and even different types of networks. All computers connected to the network can communicate and interact as long as they comply with this protocol.

In layman's terms, Internet data can travel tens of thousands of kilometers to reach the computer users who need it. This is mainly because the Internet world has formed a unified information dissemination mechanism. That is to say, Internet devices follow a unified law-TCP/IP protocol when disseminating information.

Understanding the TCP/IP protocol is of great significance to mastering the Internet and blockchain. After the invention of TCP/IP in 1974, the entire Internet was between the underlying hardware devices, the intermediate network protocols and the network Addresses have always been relatively stable, but an endless stream of innovative applications are emerging at the top application layer, including news, e-commerce, social networks, QQ, WeChat, and blockchain technology.

In other words, blockchain is in the technological ecology of the Internet.It is a new technology on the top layer of the Internet - the application layer. Its emergence, operation and development have not affected the underlying infrastructure and communication protocols of the Internet. It is still one of the many software technologies that operate according to the TCP/IP protocol.

2. Cisco router technology born in 1984: an imitation of blockchain technology

In December 1984, Cisco was established in the United States. The founder was a professor from Stanford University. A couple, Leonard Posak, director of the computer center, and Sandy Lerner, director of the business school's computer center, designed a networking device called a "multiprotocol router" that was placed on the Internet's communication lines to help data Get from one end of the Internet to the other thousands of kilometers away accurately and quickly.

In the entire Internet hardware layer, tens of millions of routers are busy working, directing the transmission of Internet information. An important function of Cisco routers is that each router saves a complete Internet device address table. Once something happens Changes will be synchronized to tens of millions of other routers (theoretically), ensuring that each router can calculate the shortest and fastest path.

When you see the operation process of the router, you will feel very familiar. That is the important feature of the blockchain later. The significance of understanding the router lies in the important features of the blockchain. It has been implemented on the router in 1984. For the router, even if the node device is damaged or attacked by hackers, it will not affect the transmission of the entire Internet information.

3. The B/S (C/S) architecture that was born with the World Wide Web: the opponent of the blockchain and the target of attempted subversion

The World Wide Web is referred to as the Web and is divided into Web clients and server. All updated information is only modified on the Web server. Thousands, tens of thousands, or even tens of millions of other client computers do not retain the information and only obtain the information data when accessing the server. This structure is often called the Internet B/S architecture is a centralized architecture. This architecture is also the most important architecture of the current Internet. Internet giants such as Google, Facebook, Tencent, Alibaba, and Amazon have all adopted this architecture.

Understanding the B/S architecture will be of great significance to the subsequent understanding of blockchain technology. The B/S architecture is that data is only stored in the central server, and all other computers obtain information from the server. Blockchain technology has tens of millions of computers without a center, and all data will be synchronized to all computers. This is the core of blockchain technology.

4. Peer-to-Peer Network (P2P): Blockchain The father of the chain and its technical basis

Peer-to-peer network P2P is another Internet infrastructure corresponding to C/S (B/S). Its characteristic is that multiple computers connected to each other are connected to each other. In a peer-to-peer position, there is no distinction between master and slave. A computer can be used as a server, setting shared resources for use by other computers in the network, and as a workstation.

Napster is one of the earliest P2P systems, mainly used for music resource sharing. Napster cannot be regarded as a true peer-to-peer network system. On March 14, 2000, a message was posted on the Slashdot mailing list of the underground hacker site in the United States, saying that AOL's Nullsoft department had released Gnutella, an open source Napster clone software.

In the Gnutella distributed peer-to-peer network model, each networked computer is functionally peer, serving as both a client and a server, so Gnutella is called the first true peer-to-peer network model. Network Architecture.

In the past 20 years, some Internet technology giants such as Microsoft and IBM, as well as liberals, hackers, and even criminals who infringe intellectual property rights, have continued to promote the development of peer-to-peer networks. Of course, those on the Internet want to strengthen information sharing. The idealists also put a lot of enthusiasm into peer-to-peer networks. Blockchain is a software application based on a peer-to-peer network architecture. It is a benchmark application for peer-to-peer networks trying to break out from the silence of the past.

5. Hash algorithm: the key to generating Bitcoin and tokens (tokens)

The hash algorithm converts numbers of any length into fixed-length values ​​using a hash function. Algorithms, famous hash functions such as: MD4, MD5, SHS, etc. It is a member of the family of cryptographic functions defined by the American National Institute of Standards and Technology.

This family of algorithms is crucial to the functioning of the entire world. From Internet application stores, emails, anti-virus software, to browsers, etc., all of them are using secure hashing algorithms. It can determine whether Internet users have downloaded what they want, and it can also determine whether Internet users are involved in man-in-the-middle attacks or network attacks. Victim of a phishing attack.

The process of blockchain and its application to generate new coins from Bitcoin or other virtual currencies is to use the function of the hash algorithm to perform operations to obtain numbers that meet the format requirements, and then the blockchain program gives Bitcoin rewards.

Mining, including Bitcoin and tokens, is actually a small mathematical game built with a hash algorithm. However, because of the fierce competition, people all over the world used powerful servers to perform calculations in order to get the rewards first. As a result, many computers on the Internet participated in this little mathematical game, which even consumed more than 40% of the electricity in some countries.

2. The birth and technical core of blockchain

The birth of blockchain should be the most unusual and mysterious invention and technology in the history of human science, because apart from blockchain, So far, there is no major invention in the history of modern science whose inventor cannot be found.

On October 31, 2008, Bitcoin founder Satoshi Nakamoto (pseudonym) published a paper on the cryptography mailing group - "Bitcoin: A Peer-to-Peer Electronic Cash System". In this paper, the author claims to have invented a new set ofAn electronic currency system that is not controlled by governments or institutions, blockchain technology is the basis for supporting the operation of Bitcoin.

The preprint address of the paper is at http://www.bitcoin.org/bitcoin.pdf. From an academic point of view, this paper is far from a qualified paper. The main body of the article is composed of 8 flow charts. It is composed of corresponding explanatory text, no nouns and terms are defined, and the format of the paper is also very irregular.

In January 2009, Satoshi Nakamoto released an application case of blockchain on the SourceForge website - the open source software of the Bitcoin system. After the release of the open source software, it is said that Satoshi Nakamoto mined approximately 1 million bits. Coin. A week later, Satoshi Nakamoto sent 10 Bitcoins to cryptography expert Hal Finney, which became the first transaction in Bitcoin history. With the booming development of Bitcoin, research on blockchain technology has also begun to show explosive growth.

It is indeed difficult to explain the blockchain to the public completely and clearly. We use Bitcoin as the object to introduce the technical characteristics of the blockchain as simply as possible but in depth.

1. Blockchain is a peer-to-peer network (P2P) software application

As we mentioned before, at the beginning of the 21st century, the Internet formed two major types of applications. Architecture, centralized B/S architecture and non-centered peer-to-peer (P2P) architecture. Many Internet giants such as Alibaba, Sina, Amazon, etc. all have centralized B/S architecture. Simply put, it is data Put it in a giant server, and our ordinary users can access the servers of Alibaba, Sina and other websites through mobile phones and personal computers.

Since the beginning of the 21st century, there have been many software applications for freely sharing music, videos, and paper materials. Most of them use a peer-to-peer network (P2P) architecture, that is, there is no central server, everyone's personal computer They are all servers and clients, with equal status. However, this type of application has never become popular. The main reasons are large resource consumption and intellectual copyright issues. Blockchain is a software application in this field.

2. Blockchain is a peer-to-peer network (P2P) software application that synchronizes information across the entire network

Peer-to-peer networks also have many application methods. In many cases, everyone is not required to Each computer keeps the same information. Everyone only stores the information they need, and downloads it to other computers when needed.

However, in order to support Bitcoin financial transactions, the blockchain requires that every transaction that occurs must be written into historical transaction records and change information be sent to all computers with Bitcoin programs installed. Every computer with Bitcoin software installed maintains the latest and complete Bitcoin historical transaction information.

The characteristics of blockchain's network-wide synchronization and network-wide backup are often referred to as blockchain information security, and the source cannot be changed. Although it is still not absolutely safe in practice, when the number of users is very largeAt the same time, it does have certain security advantages in preventing information tampering.

3. Blockchain is a peer-to-peer network (P2P) software application that uses a hash algorithm to generate "tokens" to synchronize information across the entire network

Area The first application of blockchain is the famous Bitcoin. When discussing Bitcoin, a term that is often mentioned is "mining". So what exactly is mining?

The metaphor is that the blockchain program gives the miners (players) 256 coins, numbered 1, 2, 3...256. Every time a Hash operation is performed, it is like tossing a coin. 256 coins are thrown at the same time. After landing, if all the coins with the first 70 numbers happen to be heads. The miner can tell the blockchain program this number, and the blockchain will reward the miner with 50 Bitcoins.

From the perspective of software programs, Bitcoin mining is a mathematical game built using the hash SHA256 function. The blockchain first stipulates a winning mode in this small game: a 256-bit hash number is given, but the last 70 bits of the hash number are all 0, and then the player (miner) continuously enters various numbers. Give the hash SHA256 function and see if you can use this function to get a number with 70 zeros. If you find one, the blockchain program will reward the player with 50 Bitcoins. Actual mining and rewards are more complex, but the above example expresses the core process of mining and obtaining Bitcoin.

When Bitcoin was born in 2009, each bounty was 50 Bitcoins. Ten minutes after its birth, the first batch of 50 Bitcoins was generated, and the total currency amount at this time was 50. Subsequently, Bitcoin increased at a rate of about 50 every 10 minutes. When the total amount reaches 10.5 million (50% of 21 million), the bounty is halved to 25. When the total amount reaches 15.75 million (new output is 5.25 million, which is 50% of 1050), the bounty is further halved to 12.5. According to the design of the Bitcoin program, the total number of Bitcoins is 21 million.

From the above introduction, Bitcoin can be seen as a guessing game based on a peer-to-peer network architecture. The Bitcoin information rewarded for each correct guess will be transmitted to all players and recorded. into each player's history database.

4. Smart contracts, tokens, ICOs and blockchain basic platforms generated by blockchain technology due to the rise of Bitcoin

From the above introduction, Bitcoin technology It is not a new technology falling from the sky, but a clever combination of various original Internet technologies, such as peer-to-peer network architecture, network-wide synchronization of routing, and network security encryption technology. It can be regarded as a combination of innovative algorithm games. .

Because Bitcoin can be exchanged for legal currency, purchased in kind, and made huge profits through appreciation, the whole world is not calm. With the attitude that if you can do it, I can do it, many people have created their own imitation Bitcoin software applications. while taking advantage of the difficulty for governments to regulate reciprocityCharacteristics of the network, various altcoins exploded alongside Bitcoin. There have been many incidents of fraud and absconding, which have gradually attracted the attention of governments around the world.

Blockchain basic platform: It is still quite technically difficult to create currency using the blockchain technology framework. At this time, basic technology platforms such as Ethereum, the blockchain basic platform, have emerged, making it convenient for ordinary people. Create a "Bitcoin"-like software program, each showing its magical powers, inviting people to join the game to mine coins, speculate on coins, and gain profits from it.

Pass or token: If each "Bitcoin" or "Altcoin" uses a hash algorithm to create a guessing game and generates its own "currency", this "currency" is collectively referred to as " "Certificate" or "Token".

ICO: Since Bitcoin and Ethereum have been exchanged with the legal currencies of various countries, when other new virtual currencies are issued, only Bitcoin and Ethereum are allowed to purchase the new issued coins. This process of issuing coins It’s called ICO. The emergence of ICO has amplified the transaction volume of Bitcoin and Ethereum. At the same time, many ICO projects are completely based on nihilistic projects, resulting in a large number of frequent fraud cases. This further deepens society’s negative understanding of virtual currencies generated by blockchain.

Smart contract: It can be seen as a software function on the blockchain. It is a program that assists various virtual currency transactions on the blockchain. The specific function is like the fund custody of Alipay on Taobao. When a user receives goods and confirms them on Alipay, the funds are automatically paid to the buyer and owner. Smart contracts also assume this intermediary payment function in blockchain applications such as Bitcoin.

3. The historical status and future prospects of blockchain technology in the Internet

1. Where does blockchain stand in Internet technology? It is a new software and architecture at the top level.

We mentioned in the previous introduction to TCP/IP that blockchain, like browsers, QQ, WeChat, online game software, mobile APPs, etc., is a software form of the top layer of the Internet - the application layer. . Its operation still relies on the TCP/IP architecture system to transmit data. But unlike most application layer software, it does not adopt the central software architecture of C/S (B/S). Instead, an unusual peer-to-peer network architecture is adopted. From this point of view, blockchain cannot subvert the Internet infrastructure.

2. Who does blockchain want to subvert? Want to subvert the B/S (C/S) structure of the World Wide Web.

It attempts to subvert the B/S, C/S structure of the World Wide Web, which was born in 1989. Said before. Since 1989, European physicist Tim Berners-Lee invented the World Wide Web and gave up applying for a patent. In the past nearly 30 years, companies including Google, Amazon, Facebook, Alibaba, Internet, Tencent and other companies have used the B/S (C/S) structure of the World Wide Web to grow into Internet giants.

In their headquarters, a powerful central server cluster has been established to store massive amounts of data. Hundreds of millions of users obtain their needs from the giant servers.This also led to the emergence of cloud computing, and then Internet giants opened up their unused central server resources to further absorb data from enterprises, governments, and individuals. Centralized Internet giants have an increasing influence on the world, countries, and Internet users.

The goal of blockchain is to try to reduce the influence of Internet giants by distributing data to each Internet user’s computer. It can be seen that the real opponent of blockchain and what it wants to subvert is the 1990 The B/S (C/S) structure born in 2007. But whether it can be subverted depends on its technical advantages and bottlenecks.

3. Technical flaws of blockchain: dilemmas caused by the pursuit of complete equality and freedom

The technical flaws of blockchain first come from its peer-to-peer network architecture. For example For example, Taobao currently has a B/S structure, and massive data is stored in the Taobao server cluster computer room. Hundreds of millions of consumers access the Taobao server website through their browsers to obtain the latest information and historical information.

If blockchain technology is used, hundreds of millions of people will retain a complete Taobao database on their personal computers or mobile phones. Every time a transaction occurs, it will be synchronized to hundreds of millions of other users. This is completely unachievable in reality. The amount of data transferred and stored is too large. It is equivalent to setting up and running hundreds of millions of Taobao websites at the same time.

Therefore, blockchain cannot be applied to projects with large amounts of data, and even smaller website projects will have difficulty using blockchain. By 2018, Bitcoin had been running for nearly 10 years, and the accumulated transaction data had brought the entire system to collapse.

So the blockchain has adopted many alternative methods, such as establishing relay nodes and lightning nodes. These two concepts can also make people confused. In layman's terms, the blockchain will ask it for The subversive object B/S structure has been studied, and a data server center has been established to become the relay node of the blockchain, which can also be accessed with a browser-like terminal. This is the lightning node of the blockchain.

This change can alleviate the technical shortcomings of the blockchain, but it does make the blockchain what it opposes, centralization. It can be seen that pure blockchain technology has major flaws due to its technical characteristics and cannot be widely used like the World Wide Web. If the technology is upgraded and some parts adopt a B/S (C/S) structure, the blockchain will become centralized. The information node no longer maintains the dream when it was born.

4. Looking at the future prospects of blockchain from the Internet brain model

We know that the Internet generally refers to the Internet that connects computer networks around the world. On this basis The development of a global Internet network covering the whole world is called the Internet, which is a network structure that is interconnected.

Since the birth of the Internet in 1969, humans have innovated in the Internet field from different directions, and there is no unified plan to build the Internet into a structure. When the wheel of time reaches 2017, with the advent of artificial intelligence, Internet of things, big data, cloud computing, robots,With the vigorous development of science and technology such as virtual reality and the industrial Internet, when humans look up to see the giant systems they have created, the model and architecture of the Internet brain have become increasingly clear.

Through nearly 20 years of development, relying on the B/S and C/S structures of the World Wide Web, Tencent QQ, WeChat, Facebook, Weibo, and Twitter Amazon have developed structures similar to neuron networks. Internet devices, especially personal computers and mobile phones, map personal data and functional space on the giant's central server through the software on the device, allowing them to add friends, communicate and transfer information. Internet giants continue to optimize the software versions of hundreds of millions of terminals through software upgrades in central server clusters. In the neurological system, this is a standard central nervous system structure.

The birth of the blockchain provides another neuron model. Instead of uniformly managing neurons in the centralized services of giants, each terminal, including personal computers and personal mobile phones, becomes an independent neuron node. , retaining an independent data space and synchronizing mutual information. In the neurological system, this is a distributed neural structure with no center and multiple neural nodes.

Interestingly, these two different types of neural structures appear in the development of the nervous system. In lower organisms, blockchain-like neural structures have appeared. There are multiple ganglia with the same functions, all of which can command body activities and reactions. However, as organisms evolve, these ganglia gradually merge. When they evolve into higher In biology, the central nervous system appeared, which contains a large number of neurons that interact with each other.

4. Judgment on the future status of blockchain in the Internet

1. Understanding of Bitcoin: a guessing game based on peer-to-peer network architecture (P2P), Through clever financial and public opinion operations, it has become a "world currency" that is not subject to government supervision.

2. Understanding of blockchain: a peer-to-peer (P2P) software application that uses a hash algorithm to generate "tokens" to synchronize information across the entire network.

3. Blockchain has specific uses, such as large-scale election voting, large-scale gambling, financial transactions that circumvent government financial supervision, etc. It still has irreplaceable uses.

4. In more cases, blockchain technology will rely on the B/S and C/S structures of the Internet to achieve functional expansion, but overall it is still a supplement to the existing technology of the Internet. Most of the application scenarios currently envisaged by blockchain can be implemented using B/S and C/S structures, with higher efficiency and more mature technology.

5. Whether from the perspective of information transmission efficiency and resource consumption, or from the evolution of the nervous system, blockchain cannot become the mainstream architecture of the Internet, let alone a subversive and revolutionary leader of the future Internet.

6. Of course, Internet giants developed with B/S and C/S structures also have their problems, but these can be gradually solved through commercial and political methods in the future.

③ Comic illustration: What is blockchain

Comic illustration: What is blockchain

What is blockchain?
Blockchain, English Blockchain, is essentially a decentralized distributed database. Anyone can become a node of this huge network as long as they set up their own server and connect to the blockchain network.
Since the blockchain is essentially a database, what exactly is stored in it? Let’s take a look at the basic unit of blockchain: Block.
A block is divided into two parts:
1. Block header
The block header stores the header information of the block, including the hash value (PreHash) of the previous block. The hash value of the block body (Hash), the timestamp (TimeStamp), etc.
2. Block body
The block body stores the detailed data (Data) of this block. This data contains several rows of records, which can be transaction information or some other information.
What does the hash value just mentioned mean?
Everyone must have heard of MD5. MD5 is a typical hash algorithm that can convert a string of plaintext of any length into a string of fixed length (128 bits). This string is the hash value.
In our blockchain, a more complex hash algorithm called SHA256 is used. After a series of complex calculations, the latest data information (such as transaction records) will eventually be converted into a 256-bit hash value string through this hash algorithm, which is the Hash in the block header. The format is as follows:

Blocks and Hash have a one-to-one correspondence, and Hash can be regarded as the unique identifier of the block.
How are different blocks related to each other? Rely on Hash and PreHash to associate. The PreHash value of each block is equal to the Hash value of the previous block.
Why do we need to calculate the hash value of the block?
Since the blockchain is a chain structure, there must be a head node (the first block) and a tail node (the last block) of the chain. Once someone calculates the hash value of the latest data in the blockchain, which is equivalent to packaging the latest transaction records, a new block will be created and connected to the end of the blockchain.
The Hash of the new block header is the hash value just calculated, and the PreHash is equal to the Hash of the previous block. The data in the block body stores the transaction records before packaging, and this part of the data information has become unmodifiable.
This process of calculating Hash values ​​and creating new blocks is called mining.
The server used for massive calculations is called a mining machine.
The workers who operate calculations are called miners.
Study on calculating hash valueWhere is the difficulty? Let’s give the most superficial explanation. The formula for calculating the hash value is as follows:
Hash = SHA-256 (Hash of the last block + basic information of the new block + transaction record information + random number)
Among them, the transaction record information is also a series of hash values, and its calculation involves a data structure Merkle Tree. Interested friends can check the relevant information, we will not introduce it for now.
The key computational difficulty here lies in the generation of random numbers. In order to increase the difficulty of Hash calculation, the wretched inventor of the blockchain requires that the first 72 bits of the Hash result must be 0. This probability is too small.
Since (the Hash of the last block + the basic information of the new block + the transaction record information) is fixed, whether the Hash that meets the requirements can be obtained depends entirely on the value of the random number. Miners must go through massive calculations and repeatedly generate random numbers in an attempt to "get lucky" before they can get the correct Hash and successfully mine.
At the same time, the block header also contains a dynamic difficulty coefficient. When the world's hardware computing power becomes faster and faster, the difficulty coefficient of the blockchain will also increase, making the entire network capable of completing the task every 10 minutes on average. A new block is generated.
Friends, do you understand how difficult mining is? It should be added that different blockchain applications are different in details. The mining rules described here take Bitcoin as an example.
Applications of Blockchain

The concept of Bitcoin (BitCoin) was first proposed by Satoshi Nakamoto in 2008, and then based on this idea, open source software and P2P built on it were designed and released. network. Bitcoin is a P2P form of digital currency. Peer-to-peer transmission means a decentralized payment system.
What is a P2P network?
Traditional currencies are uniformly issued by the central bank, and all personal savings are uniformly managed by banks. This is a typical centralized system.
Bitcoin is deployed on a decentralized network composed of many peer nodes around the world. Every node is qualified to record and issue this digital currency.
As for the underlying data storage of Bitcoin, it is based on blockchain technology. Each transaction in Bitcoin corresponds to a row in the block body data. A simple diagram is as follows:
Each row of the transaction record contains a timestamp, transaction details, and digital signature.
The table is only for ease of understanding. The actual stored transaction details are anonymous, and only the wallet addresses of the payer and payee are recorded.
As for digital signatures, they can be understood as anti-counterfeiting marks for each single transaction, generated by an asymmetric encryption algorithm.
Let’s talk about the rewards for Bitcoin miners:
The Bitcoin protocol stipulates that miners who mine new blocks will receive rewards.The reward has been 50 Bitcoins since 2008, then halved every 4 years, and is currently 12.5 Bitcoins in 2018. The new Bitcoins in circulation are all born in this way. No wonder everyone is so eager to mine Bitcoins!
Advantages and Disadvantages of Blockchain
Advantages of Blockchain:
1. Decentralization
Blockchain does not rely on a central node. The data of the entire system is All peer nodes in the entire network are jointly maintained and can store and verify data. In this way, unless the attacker hacks more than half of the nodes in the entire network, the entire system will not be destroyed.
2. Information cannot be tampered
The data in the block cannot be tampered with. Once the data is tampered with even a little bit, the hash value corresponding to the entire block will change accordingly, and it will no longer be a valid hash value, and the subsequent linked blocks will also be broken.
Disadvantages of blockchain:
1. Excessive consumption of energy
To generate a new block, a large amount of server resources must be used to perform a large number of unnecessary trial calculations, which seriously consumes electricity.
2. Network delay of information
Take Bitcoin as an example. Any transaction data needs to be synchronized to all other nodes. The synchronization process will inevitably be affected by network transmission delay, resulting in a long time consuming.
A few additional points:
1. Part of the content of this comic refers to Ruan Yifeng’s blog post "Blockchain Introductory Tutorial". I would like to thank this great master for his popular science.
2. Due to limited space, the knowledge about Merkle Tree and asymmetric encryption has not been discussed in detail for the time being. Interested friends can check the information for further study.

④ 108 knowledge points for getting started with blockchain

108 essential knowledge points for getting started with blockchain

(Welcome to communicate with fellow fans)

1. What is a blockchain

The information of multiple transactions and the information indicating the block are packaged together. The verified package is the block.

Each block stores the hash value of the previous block, creating a relationship between blocks, that is to say, a chain. Together they are called blockchain.

2. What is Bitcoin

The concept of Bitcoin was proposed by Satoshi Nakamoto in 2009, with a total number of 21 million. The Bitcoin chain generates a block approximately every 10 minutes, and this block is mined by miners for 10 minutes. As a reward to miners, a certain number of Bitcoins will be issued to miners, but this certain number is halved every four years. Now it's 12.5. If this continues, all Bitcoins will be available in 2040.

3. What is Ethereum

Ethereum andThe biggest difference with Bitcoin is the presence of smart contracts. This allows developers to develop and run various applications on it.

4. Distributed ledger

It is a database that is shared, replicated and synchronized among network members. To put it bluntly, all users on the blockchain have accounting functions and the content is consistent, which ensures that the data cannot be tampered with.

5. What is quasi-anonymity?

I believe everyone has a wallet, and the wallet address (a string of characters) used to send transactions is quasi-anonymity.

6. What is open transparency/traceability

The blockchain stores all data from history to the present, anyone can view it, and can also view any data in history.

7. What is tamper-proof

Historical data and current transaction data cannot be tampered with. The data is stored in the block on the chain and has a hash value. If the block information is modified, its hash value will also change, and the hash values ​​of all blocks following it must also be modified to form a new chain. At the same time, the main chain is still conducting transactions to generate blocks. The modified chain must always generate blocks synchronously with the main chain to ensure that the length of the chain is the same. The cost is too high, just to modify a piece of data.

8. What is anti-DDoS attack

DDoS: Hackers control many people’s computers or mobile phones and allow them to access a website at the same time. Since the bandwidth of the server is limited, a large amount of traffic The influx of data may cause the website to fail to function properly, resulting in losses. However, the blockchain is distributed and there is no central server. If one node fails, other nodes will not be affected. Theoretically, if more than 51% of the nodes are attacked, problems will occur.

9. Definition of main chain

Taking Bitcoin as an example, at a certain point in time, a block is mined by two miners at the same time, and then 6 blocks are generated first. The chain of blocks is the main chain

10. Single chain/multi-chain

Single chain refers to the data structure that handles everything on one chain. The core essence of the multi-chain structure is composed of public chain + N sub-chains. There is only one, but in theory there can be countless sub-chains, and each sub-chain can run one or more DAPP systems

11. Public chain/alliance chain/private chain

Public Chain: Everyone can participate in the blockchain

Alliance chain: Only alliance members are allowed to participate in accounting and query

Private chain: Writing and viewing permissions are only controlled by one person In the hands of the organization.

12. Consensus layer, data layer, etc.

There are six overall structures of the blockchain: data layer, network layer, consensus layer, incentive layer, contract layer, and application layer. dataLayer: a layer that records data, belonging to the underlying technology; network layer: a structure for building a blockchain network, which determines how users are organized. Consensus layer: Provides a set of rules to allow everyone to reach agreement on the information received and stored. Incentive layer: Design incentive policies to encourage users to participate in the blockchain ecosystem; Contract layer: Generally refers to "smart contracts", which are a set of contract systems that can be automatically executed and written according to their own needs. Application layer: Applications on the blockchain, similar to mobile apps. Former Distributed Storage R&D Center

13. Timestamp

The timestamp refers to January 1, 1970 Day 0 hours 0 minutes 0 seconds 0... The total number of seconds from the current time to now, or the total number of nanoseconds and other very large numbers. Each block is generated with a timestamp indicating when the block was generated.

14. Block/block header/block body

Block is the basic unit of blockchain, and block header and block body are components of blockchain. The information contained in the block header includes the hash of the previous block, the hash of this block, timestamp, etc. The block body is the detailed data in the block.

15. Merkle tree

Merkle tree, also called binary tree, is a data structure for storing data. The bottom layer is the original data contained in all blocks, and the upper layer is each The hash value of a block, the hash value of this layer is combined in pairs to generate a new hash value, forming a new layer, and then upwards layer by layer, until a hash value is generated. Such a structure can be used to quickly compare large amounts of data, and you can quickly find the bottom-level historical data you want without downloading all the data.

16. What is expansion?

The size of a Bitcoin block is about 1M and can save 4,000 transaction records. Expansion means making the block larger so that more data can be stored.

17. What is a chain?

Each block will save the hash of the previous block, creating a relationship between the blocks. This relationship is a chain. Data such as block transaction records and status changes are stored through this chain.

18. Block height

This is not the height mentioned in terms of distance. It refers to the total number of blocks between the block and the first block on the chain. This height indicates which block it is, and is just for identification purposes.

19. Fork

Two blocks were generated at the same time (the transaction information in the block is the same, but the hash value of the block is different), and then in Two chains are forked from these two blocks. Whoever generates 6 blocks from these two links first will be the main chain, and the other chain will be discarded.

20. Ghost Protocol

Mining pools with high computing power can easily generate blocks faster than mining machines with low computing power, resulting in most blocks on the blockchain being generated by these mining pools with high computing power. However, the blocks generated by mining machines with low computing power are not stored on the chain because they are slow, and these blocks will be invalid.

The ghost protocol allows blocks that should be invalidated to remain on the chain for a short time, and can also be used as part of the proof of work

. In this way, miners with small computing power will contribute more to the main chain, and large mining pools will not be able to monopolize the confirmation of new blocks.

21. Orphan block

As mentioned before, orphan blocks are blocks generated at the same time. One of them forms a chain, and the other does not form a chain. Then this block that does not form a chain is called an orphan block.

22. Uncle block

The orphan block mentioned above, through the ghost protocol, makes it part of the proof of work, then it will not be discarded and will be saved in the main chain superior. This block is next

23 replay attack

The hacker resends the message that has been sent to the server. Sometimes this can deceive the server into multiple responses.

24. Directed acyclic graph

Also called data set DAG (directed acyclic graph), DAG is an ideal multi-chain data structure. Most of the blockchains mentioned now are single chains, that is, one block is connected to another block, and DAG is multiple blocks connected. The advantage is that several blocks can be generated at the same time, so the network can process a large number of transactions at the same time, and the throughput will definitely increase. However, there are many shortcomings and it is currently in the research stage.

25. What is mining

The mining process is to perform a series of conversions, connections and hash operations on the above six fields, and continue to try them one by one. The random number you are looking for, and finally successfully find a random number that meets the conditions: the value after hashing is smaller than the hash value of the preset difficulty value, then the mining is successful, and the node can broadcast the area to neighboring nodes. block, neighboring nodes receive the block and perform the same operation on the above six fields to verify compliance, and then forward it to other nodes. Other nodes also use the same algorithm to verify. If there are 51% of nodes in the entire network If all verifications are successful, even if this block is truly "mined" successfully, each node will add this block to the end of the previous block, delete the list in the block that is the same as its own record, and resurrect again. the above process. Another thing to mention is that regardless of whether the mining is successful or not, each node will pre-record the reward of 50 Bitcoins and the handling fees of all transactions (total input-total output) in the first item of the transaction list (this is " The most fundamental purpose of "mining" is also the fundamental reason to ensure the long-term stable operation of the blockchain), the output address is the address of this node, but if the mining is unsuccessful, thisThe transaction is voided and there is no reward. Moreover, this transaction called "production transaction" does not participate in the "mining" calculation.

26. Mining machines/mining farms

Mining machines are computers with various configurations, and computing power is the biggest difference between them. A place where mining machines are concentrated in one place is a mining farm

27. Mining pool

Miners join together to form a team, and the computer group under this team is a mining pool. Mining rewards are distributed based on your own computing power contribution.

28. Mining difficulty and computing power

Mining difficulty is to ensure that the interval between generating blocks is stable within a certain short time, such as Bitcoin is issued in 10 minutes

p>

Block 1. The computing power is the configuration of the mining machine.

29. Verification

When verification in the blockchain is a confirmation of the legality of the transaction, each node will verify the transaction once when the transaction message is propagated between nodes. Whether the transaction is legal. For example, verify whether the syntax of the transaction is correct, whether the transaction amount is greater than 0, whether the entered transaction amount is reasonable, etc. After passing the verification, it will be packaged and handed over to the miners for mining.

30. Transaction broadcast

The node sends information to other nodes through the network.

31. Mining fees

For the blockchain to work non-stop like a perpetual motion machine, miners need to maintain the system. Therefore, the miners must be given favorable fees to make it sustainable.

32. Transaction confirmation

When a transaction occurs, the block recording the transaction will be confirmed for the first time, and will be confirmed in every area on the chain after the block. Block is reconfirmed: When the number of confirmations reaches 6 or more, the transaction is generally considered safe and difficult to tamper with.

33. Double transaction

That is, I have 10 yuan, I use the 10 yuan to buy a pack of cigarettes, and then instantly use the 10 yuan that has not yet been paid. Bought another cup of coffee. So when verifying the transaction, you need to confirm whether the 10 yuan has been spent.

34. UTXO unspent transaction output

It is a data structure containing transaction data and execution code, which can be understood as digital currency that exists but has not yet been consumed.

35. Transactions per second TPS

That is throughput, tps refers to the number of transactions the system can process per second.

36. Wallet

Similar to Alipay, it is used to store digital currencies, and blockchain technology is more secure.

37. Cold wallet/hot wallet

A cold wallet is an offline wallet. The principle is to store it locally and use QR code communication to prevent the private key from touching the Internet. hotA wallet is an online wallet. The principle is to encrypt the private key and store it on the server. When it is needed, it is downloaded from the server and decrypted on the browser side.

38. Software Wallet/Hardware Wallet

A software wallet is a computer program. Generally speaking, a software wallet is a program that interacts with the blockchain and allows users to receive, store, and send digital currencies and can store multiple keys. Hardware wallets are smart devices that specialize in handling digital currencies.

39. Airdrop

The project sends digital currency to each user’s wallet address.

40. Mapping

Mapping is related to the issuance of blockchain currency and is a mapping between chains. For example, there are some blockchain companies that have not completed the development of the chain in the early stage. They rely on Ethereum to issue their own currency. The issuance and transactions of the early currency are all operated on Ethereum. With the development of the company, the company's own chain development has been completed. The company wants to map all the previous information on Ethereum to its own chain. This process is mapping.

41. Position

Refers to the ratio of the investor’s actual investment to the actual investment funds

42. Full position

All funds are bought Enter Bitcoin

43. Reduce the position

Sell some of the Bitcoins, but not all of them

44. Heavy positions

Compared with Bitcoin, Bitcoin accounts for a larger share of funds

45. Short position

Compared with Bitcoin, the share of funds is larger

46. Short position

Sell all the Bitcoins you hold and convert them all into funds

47. Stop loss

After obtaining a certain profit, sell the Bitcoin held to keep the profit

48. Stop loss

After losses reach a certain level, sell the Bitcoins you hold to prevent further losses

49. Bull market

Prices continue to rise and the outlook is optimistic

50. Bear market

The price continues to fall, and the outlook is bleak

51. Long (long)

The buyer believes that the currency price will rise in the future, buys the currency, and waits for the currency price After rising, sell at a high price to take profits

52. Short position (short selling)

The seller believes that the currency price will fall in the future, and sells the currency he holds (or borrows it from the trading platform) currency) and sell, wait for the currency price to fall, buy at a low price to take profits

53. Open a position

Buy virtual currencies such as Bitcoin

54. Cover the position

Buy Bitcoin and other virtual currencies in batches, for example: buy 1 BTC first, and then buy 1 BTC later

55. Full position

Buy all the funds into a certain virtual currency at once

56. Rebound

When the currency price falls, the price rebounds and adjusts because it falls too fast

57. Consolidation (sideways)

The price fluctuation range is small, and the currency price is stable

58. Yin fall

The currency price declines slowly

< p> 59. Diving (waterfall)

The currency price fell rapidly and to a large extent

60. Cutting meat

After buying Bitcoin, the currency price fell. Sell ​​Bitcoin at a loss to avoid further losses. Or after borrowing the currency to go short, the currency price rises, and you buy Bitcoin at a loss

61. Hold on

Expect the currency price to rise, but unexpectedly the currency price falls after buying; or expect the currency price fell, but unexpectedly, after selling, the currency price rose

62. Unwinding

After buying Bitcoin, the currency price fell, causing a temporary book loss, but then the currency price rebounded and the loss was reversed To make a profit

63. Go short

After selling Bitcoin because of the bearish market outlook, the price of the currency continued to rise, and I was unable to buy it in time, so I failed to make a profit

64. Overbought

The currency price continues to rise to a certain height, the buyer's power is basically exhausted, and the currency price is about to fall

65. Oversold

The currency price continues to fall to a certain low, the seller's power has basically been exhausted, and the currency price is about to rise

66. Lure bulls

The currency price has been consolidating for a long time, and it is more likely to fall. Most of the short sellers have sold Bitcoin, and suddenly the short sellers pulled up the price of the currency, inducing the long parties to think that the price of the currency will rise and buy one after another. As a result, the short sellers suppressed the price of the currency and locked up the long parties.

67. Lure shorts

After buying Bitcoin, bulls deliberately suppress the price of the currency, making short sellers think that the price of the currency will fall and sell them one after another. As a result, they fall into the trap of bulls

68. What is NFT

The full name of NFT is "Non-Fungible Tokens", which is a non-fungible token. Simply put, it is an indivisible token on the blockchain. Copyright certificate is mainly used to confirm and transfer the rights of digital assets. The difference from digital currency is that it is unique and indivisible. In essence, it is a unique digital asset.

69. What is the Metaverse

The Metaverse is a collection of virtual time and space, consisting of a series of enhanced phenomena.It is composed of reality (AR), virtual reality (VR) and the Internet (Internet), among which digital currency carries the function of value transfer in this world.

70. What is DeFi

DeFi, the full name is Decentralized Finance, which is "decentralized finance" or "distributed finance". "Decentralized finance", as opposed to traditional centralized finance, refers to various financial applications based on open decentralized networks. The goal is to establish a multi-level financial system based on blockchain technology and cryptocurrency. As a basis, re-create and improve the existing financial system

71. Who is Satoshi Nakamoto?

Satoshi Nakamoto is the developer and founder of Bitcoin. Satoshi Nakamoto published the Bitcoin white paper on November 1, 2008, and mined Bitcoin for the first time on January 3, 2009. Whoever can use the Bitcoin in the genesis block is Satoshi Nakamoto himself, so who Is it Satoshi Nakamoto? There have been many "Satoshi Nakamotos" in history: In 2013, someone revealed that Mochizuki Shinichi, who had made outstanding contributions in the field of mathematics, was Satoshi Nakamoto, but no direct evidence was provided. In 2014, hackers broke into the mailbox used by Satoshi Nakamoto and found the owner of the mail, Dorian Nakamoto. Later, Dorian said that he only obtained the mailbox address and password by chance, not Nakamoto. Cong. In 2016, Craig Wright said that he was Satoshi Nakamoto and could provide Satoshi Nakamoto's private key. But later, Wright withdrew his statement because he could not face everyone's doubts.

72. Bitcoin is different from Q Coin

Bitcoin is a decentralized digital asset with no issuing entity. Q Coin is an electronic currency issued by Tencent. It is similar to electronic points, but it is not actually a currency. Q Coin requires a centralized issuing institution. Q Coin can only be recognized and used because of the credit endorsement of Tencent. The scope of use is also limited to Tencent's games and services. The value of Q coins is entirely based on people's trust in Tencent.

Bitcoin is not issued through a centralized institution, but it is widely recognized around the world because Bitcoin can self-certify its trust. The issuance and circulation of Bitcoin are jointly accounted for by miners across the entire network, and are not A central authority is also needed to ensure that no one can tamper with the ledger.

73. What is a mining machine?

Taking Bitcoin as an example, a Bitcoin mining machine is a professional equipment that competes for accounting rights by running a large amount of calculations to obtain new Bitcoin rewards. It is generally composed of a mining chip, a heat sink and a fan, and only performs A single calculation program consumes a lot of power. Mining is actually a competition between miners for computing power. Miners with more computing power have a greater probability of mining Bitcoin. As the computing power of the entire network increases, traditional equipment (CPU, GPU)It is becoming more and more difficult to mine bits, and people have developed chips specifically for mining. The chip is the core part of the mining machine. The operation of the chip will generate a large amount of heat. In order to dissipate heat, Bitcoin mining machines are generally equipped with heat sinks and fans. Users download Bitcoin mining software on their computers, use the software to assign tasks to each mining machine, and then start mining. Each currency has a different algorithm and requires different mining machines.

74. What is quantitative trading?

Quantitative trading, sometimes also called automated trading, refers to the use of advanced mathematical models to replace human subjective judgments, which greatly reduces the impact of investor sentiment fluctuations and avoids extreme fanaticism or pessimism in the market. make irrational investment decisions. There are many types of quantitative trading, including cross-platform trading, trend trading, hedging, etc. Cross-platform trading means that when the price difference between different target platforms reaches a certain amount, sell on the platform with a higher price and buy on the platform with a lower price.

75. Blockchain asset over-the-counter trading

Over-the-counter trading is also called OTC trading. Users need to find their own counterparties and do not need to match the transaction. The transaction price is determined by negotiation between the two parties. The two parties can fully communicate through face-to-face negotiation or telephone communication.

76. What is a timestamp?

The blockchain ensures that each block is connected sequentially through timestamps. Timestamps enable every piece of data on the blockchain to have a time stamp. Simply put, timestamps prove when something happened on the blockchain and cannot be tampered with by anyone.

77. What is a blockchain fork?

Upgrading software in a centralized system is very simple, just click "Upgrade" in the app store. However, in decentralized systems such as blockchain, "upgrading" is not that simple, and a disagreement may even cause a blockchain fork. Simply put, a fork refers to a disagreement when the blockchain is "upgraded", resulting in a fork in the blockchain. Because there is no centralized organization, every code upgrade of digital assets such as Bitcoin needs to be unanimously recognized by the Bitcoin community. If the Bitcoin community cannot reach an agreement, the blockchain is likely to form a fork.

78. Soft fork and hard fork

Hard fork means that when the Bitcoin code changes, the old nodes refuse to accept the blocks created by the new nodes. Blocks that do not comply with the original rules will be ignored, and miners will follow the original rules and create new blocks after the last block they verified. A soft fork means that old nodes are not aware of the changes to the Bitcoin code and continue to accept blocks created by new nodes. Miners may work on blocks they have no understanding of, or validation of. Both soft forks and hard forks are "backwards compatible" to ensure that new nodes can verify the blockchain from scratch. Backward compatibility means that new software accepts data or code generated by old software. For example, Windows 10 can runRun Windows XP applications. Soft forks can also be "forward compatible".

79. Classification and application of blockchain projects

Judging from the current mainstream blockchain projects, blockchain projects mainly fall into four categories: Category 1: Currency; The second category: platform category; the third category: application category; the fourth category: asset tokenization.

80. USDT against the US dollar

USDT is Tether USD, a token launched by Tether that is against the US dollar (USD). 1USDT=1 US dollar, users can use USDT and USD for 1:1 exchange at any time. Tether implements a 1:1 reserve guarantee system, that is, each USDT token will have a reserve guarantee of 1 US dollar, which supports the stability of the USDT price. The unit price of a certain digital asset is USDT, which is equivalent to its unit price in US dollars (USD).

81. Altcoins and alternative coins

Altcoins refer to blockchain assets that use the Bitcoin code as a template and make some modifications to its underlying technology blockchain, among which Those with technological innovations or improvements are also called alternative coins. Because the Bitcoin code is open source, the cost of plagiarism in Bitcoin is very low. You can even generate a brand new blockchain by simply copying the Bitcoin code and modifying some parameters.

82. Three major exchanges

Binance

Okex

Huobi

83. Market software

Mytoken

Non-small account

84. Information website

Babbitt

Golden Finance

Coin World News

85. Blockchain Browser

BTC

ETH

BCH

< p> LTC

ETC

86. Wallet

Imtoken

Bitpie

MetaMask (Little Fox)

87. Decentralized exchange

uniswap

88. NFT exchange

< p> Opensea

Super Rare

89. Ladder

Bring your own, buy a reliable ladder

90. Platform currency

The digital currency issued by the platform is used to deduct handling fees and transactionsEtc.

91. Bull market, bear market

Bull market: rising market

Bear market: falling market

92. Blockchain 1.0

p>

A currency trading system based on distributed ledgers, represented by Bitcoin

93. Blockchain 2.0

Contract blocks represented by Ethereum (smart contracts) Chain technology is 2.0

94. Blockchain 3.0

In the era of intelligent Internet of Things, it goes beyond the financial field to provide decentralized solutions for various industries

95. Smart Contract

Smart Contract is a computer protocol designed to disseminate, verify or execute contracts in an information-based manner. Simply put, an electronic contract is set in advance. Once both parties confirm, the contract automatically implement.

96. What is a token?

The token economy is an economic system with Token as the only reference standard, which is equivalent to a pass. If you own Token, you have rights and interests, and you have the right to speak.

97. The difference between big data and blockchain

Big data is the means of production, AI is the new productivity, and the blockchain is the new production relationship. Big data refers to a collection of data that cannot be captured, managed and processed within a certain time range using conventional software tools. It is a massive, high-growth and high-volume data set that requires new processing models to have stronger decision-making power, insight discovery and process optimization capabilities. Diverse information assets. Simply understood, big data is massive data accumulated over a long period of time and cannot be obtained in the short term. Blockchain can be used as a way to obtain big data, but it cannot replace big data. Big data is only used as a medium running in the blockchain and has no absolute technical performance, so the two cannot be confused. (A simple understanding of production relations is labor exchange and consumption relations. The core lies in productivity, and the core of productivity lies in production tools)

98. What is ICO?

ICO, Initial Coin Offering, is the initial public offering of tokens, which is crowdfunding in the blockchain digital currency industry. It is the most popular topic and investment trend in 2017, and the country launched a regulatory plan on September 4. Speaking of ICO, people will think of IPO, and the two are fundamentally different.

99. Five characteristics of digital currency

The first characteristic: decentralization

The second characteristic: having open source code

The third feature: independent electronic wallet

The fourth feature: constant issuance

The fifth feature: global circulation

100. What is decentralization?

It has no issuer, does not belong to any institution or country, and is a publicly issued currency designed, developed and stored on the Internet by Internet network experts.

100. What is measurement (scarcity)?

Once the total amount of issuance is set, it is permanently fixed, cannot be changed, cannot be over-issued at will, and is subject to global Internet supervision. Because the difficulty of mining and mining changes over time, the longer the time, the greater the difficulty of mining, and the fewer coins are mined, so it is scarce.

101. What is open source code?

The alphanumeric code is stored on the Internet. Anyone can find out the source code of its design, everyone can participate, can mine it, and it is open to the world.

102. What is anonymous transaction? Private wallet private?

Everyone can register and download the wallet online without real-name authentication. It is completely composed of encrypted digital codes. It can be sent and traded globally in real-time point-to-point without resorting to banks or any institutions. It cannot be traced by anyone without my authorization. ,Inquire.

103. What is a contract transaction?

A contract transaction refers to an agreement between a buyer and seller to receive a certain amount of an asset at a specified price at a certain time in the future. The objects of contract trading are standardized contracts formulated by the exchange. The exchange stipulates standardized information such as commodity type, transaction time, quantity, etc. A contract represents the rights and obligations of the buyer and seller.

104. Digital Currency Industry Chain

Chip manufacturers, mining machine manufacturers, and mining machine agents mine and export to exchanges for retail investors to speculate in coins< /p>

105. Who is Bei Feng?

Beifeng: Digital currency value investor

Investment style: Steady

106. Build a community? < /p>

Reasonable layout, scientific operation, prudent and conservative, earning periodic money

Welcome currency friends and seek common development.

⑤ Introduction to Blockchain What you need to know!

What is a blockchain?
Literally: a blockchain is a chain composed of small blocks that record various information, similar to what we will Bricks are stacked one after another, and they cannot be removed after being stacked. Each brick also has various information written on it, including: who stacked it, when it was stacked, what material the brick was made of, etc. You can use this information There is no way to modify it.
Viewed from a computer: DistrictBlockchain is a relatively special distributed database. A distributed database stores data information on each computer separately, and the stored information is consistent. If one or two computers in Taiwan are broken, the information will not be lost, and you can still view it on other computers.
Blockchain is distributed, so it has no central point. Information is stored in all nodes that join the blockchain network, and the data of the nodes is synchronized. A node can be a server, laptop, mobile phone, etc.
What you need to know is that the data stored in these nodes are exactly the same.
Blockchain Features
Decentralization: Because it is distributed storage, there is no central point. It can also be said that each node is a central point. Applications in life do not require a third-party system (bank , Alipay, real estate agencies, etc. are all third parties).
Openness: The system data of the blockchain is open and transparent, and everyone can participate. For example, when renting a house, you can know the previous rental information of the house and whether there have been any problems. Of course, some individuals here Private information is encrypted.
Autonomy: The blockchain adopts consensus-based specifications and protocols (such as a set of open and transparent algorithms), and then each node operates according to this specification, so that everything is done by machines and there is no human touch. Element. This changes trust in people to trust in machines, and any human intervention has no effect.
Information cannot be tampered with: If the information is stored in the blockchain, it will be saved permanently and there is no way to change it. As for the 51% attack, it is basically impossible to achieve.
Anonymity: There is no personal information on the blockchain because it is all encrypted and is a string of letters and numbers, so your ID card information and phone number will not be resold. Phenomenon.
Block structure
A block contains two parts:
1. Block header (Head): records the meta-information of the current block
2. Block body (Body): actual data
>Contains data as shown in the figure below:
How blockchain works
Let’s take transfer as an example:
Currently our transfers are centralized, and the bank is a centralized ledger. For example, there is 400 in account A There are 100 yuan in account B.
When A wants to transfer 100 yuan to B, A needs to submit a transfer application through the bank. After the bank verification is passed, 100 yuan will be deducted from A's account and 100 yuan will be added to B's account.
After calculation, the balance of account A after deducting 100 is 300 yuan, and the balance of account B after adding 100 is 200 yuan.
The steps for transferring money on the blockchain are: A wants to transfer 100 yuan to B. A will tell everyone about the transfer on the Internet, and everyone will check whether there is enough money in A's account. Complete the transfer. If the verification is passed, everyone will record this information.In the blockchain on his own computer, and the information entered by everyone is synchronized and consistent, A successfully transferred 100 yuan to B's account. You can see that there is no bank involved.
Related questions
What is the relationship between blockchain and Bitcoin?
Bitcoin was proposed by Satoshi Nakamoto in 2009, and then the blockchain technology was refined with reference to the implementation of Bitcoin.
If Bitcoin is noodles, then blockchain is flour. Later, everyone discovered that flour can be used to make steamed buns and steamed buns in addition to noodles.
Why do I need to help you store block information?
I don’t have time to do it without profit. To put it simply, you help me store information and I will give you corresponding rewards.
Key technical points that need to be understood in blockchain?
Use Hash and asymmetric encryption to ensure that data cannot be tampered with:
Hash: y = hash(x), perform a hash operation on x to obtain y , the original information x can be hidden, because you cannot calculate x through y, thus achieving anonymity.
Asymmetric encryption: The public key and the private key are a pair. If the public key is used to encrypt the data, only the corresponding private key can be used to decrypt it; if the private key is used to encrypt the data, then only It can be decrypted with the corresponding public key.
Consensus algorithm: Ensure data consistency between nodes.
Is there a sentence or two that can explain the blockchain?
Yes.
Mahjong is a traditional Chinese blockchain project. A group of four miners work together. The miner who first collides with the correct hash value of 13 numbers can obtain the accounting rights and be rewarded.

⑥ Explain blockchain in vernacular

img src=' https://p26 . toutiaoimg.com/large/39b 70000088 e 51 B3 c 258 '/

Recently, various ICO financial scams have been blocked in China, but this does not hinder the vigorous development of blockchain technology. After all, technology is innocent and can bring benefits to people. As for how to use it, it depends on people to operate it. If the operation is good, you can recommend development. If the operation is not good, it is like the major ICO projects. Find some knowledge for Internet celebrities to conduct so-called illegal fund-raising and financial fraud.

After talking for a long time, what is blockchain? When it comes to blockchain, the first thing that comes to mind for many people is Bitcoin. We need to solve a problem. Bitcoin is a blockchain, but blockchain is not Bitcoin. Simply put, blockchain is distributed ledger technology (DLT), not a token. It has many characteristics, such as decentralization, traceability, and difficulty in tampering.

(1) Blockchain is a distributed database

First of all, this is a decentralized distributed architecture system. Therefore, having only one central server or node is not called a blockchain. For example, if you go to Taobao to buy a mobile phone, you and the seller are strangers and have no basis for trust. If you give the money to the seller first, the sellerIt is very likely that they have blocked you by not delivering the goods, and then your mobile phone money will be gone. If the seller ships first, do you pay? It is possible that you do not pay the seller after receiving the goods, and one party may lose money anyway. At this time, a third-party guarantee is needed to solve the trust problem. Just like Alipay now, you give money to Alipay and the seller will deliver the goods. When you receive the goods, the seller will receive the money.

The above example is a centralized system because all guarantee work is handled by Bora, a third-party payment company. Suppose one day Alipay wants to tamper with data, neither buyers nor sellers can do anything because all authority is in the hands of one company.

At this time, a distributed database is needed. This third party is no longer Alipay, but thousands of monitors. When you buy a mobile phone on Taobao, you will shout to everyone that I am going to XXX to buy a mobile phone, and I paid XXX yuan. The other person will yell like everyone else. I collected XXX’s mobile phone bill and sent it over. In this way, everyone knows about this transaction and everyone is recording this transaction, so it is useless if one or two nodes have problems or malicious behavior, because most nodes have recorded this matter.

(B) Blockchain uses encryption technology to ensure data security

There are two important points here: 1. Crypto-enabled hash function 2. Asymmetric encryption.

If you are interested in specific concepts, you can go online, but people without basic knowledge may not be able to understand it, because these two points are too professional. In fact, if you only know the use of blockchain, you don’t need to have an in-depth understanding of it. It is also a technical concept. All you need to know is that blockchain relies on these technical points to ensure data security and is not easily tampered with. Of course, many people say that these two points can guarantee 100% non-tampering. I want to be a little conservative here. As an author who works in the security industry, I have always been skeptical about 100% security, so it may be more appropriate to call it difficult to be tampered with.

I will briefly introduce these two concepts and try to explain them clearly in plain English.

1. Cryptographic Hash Function

This is mainly used to verify the integrity of information. For example, I sent a message to the company leader saying that I was sick on Friday and needed to take a day off. At this time, a hash value will be generated based on the message I sent, such as: 123456. At this point, when the leader receives this message, a hash value is also generated. Because the content of the message I sent has not changed (it has not been tampered with), the hash value remains unchanged, still: 123456. This is if someone wants to tamper with this news and get sick on Friday and need to take a year off. At this time, the hash value will change, such as: 123489. That's when we learned our information had been tampered with.

2. Asymmetric encryption

It is mainly used for information encryption and authentication. It is actually two keys, one is called the public key and the other is called the private key. Public key encryption, private key decryption.

A public key is a key that everyone has. You own it, I own it. We can all encrypt with this key, but when decrypting it must be decrypted with my private key. if you don't have meWith the private key, you can't decrypt it.

(C) The blockchain uses a consensus algorithm to reach consensus on new data.

The role of the consensus algorithm is to enable all nodes to reach a consensus on the new block. In other words, everyone must approve the new block.

For a centralized deployment system, this is simple, everything is controlled by the center, but in the distributed system of the blockchain, it is very complicated. For example, there are three nodes. A said he bought a mobile phone from XXX store and paid for it, B said he didn’t pay, and C said he didn’t pay enough. Then who do you listen to? What's more, blockchain technology is not as simple as three nodes, but a huge distributed system.

This is when a solution is needed. There is a corresponding problem in computer science called the "Byzantine Universal Problem" or "Byzantine Fault Tolerance" (BFT). This question was raised not because of Bitcoin, but because of a special background.

Early aircraft had three independent control systems. Why do we need three independent control systems? For example, in an emergency, there is a plane opposite. How to judge whether you should hide? If there is only one system, there is no choice, which is equivalent to centralized deployment. If the system breaks, you're dead. What if one of the two systems breaks? The good ones are said to hide, and the bad ones are said not to hide. The computer cannot judge the final result. Therefore, three independent systems are needed to support it, and the probability of two total failures is still very small. But this only takes into account injuries. What should I do if there is a malicious system? Is three enough? The answer is no, we need four systems to maintain consensus.

The use of blockchain is similar, because it is supported by a huge number of nodes, and each node is an independent system without interfering with each other. We can assume that the number of failed nodes and malicious nodes is limited, so it will not cause abnormal consistency of data.

Related questions and answers: What is blockchain? What is the use?

Blockchain is a new computing paradigm and distributed infrastructure that uses fast chain data structures, distributed node consensus algorithms, cryptography and smart contracts based on automated script codes to produce, verify, store and transmit data. It can also be said that blockchain is a distributed ledger technology that can provide a decentralized trust mechanism in a non-trust environment, allowing multi-party participants to conduct secure and trust-based transactions without intermediaries.

The core advantage of blockchain technology is decentralization. It can realize decentralized credit-based transactions in a distributed system where nodes do not need to trust each other by using data encryption, timestamps, distributed consensus and economic incentives. Point-to-point transactions, coordination and collaboration provide solutions to the common problems of high cost, low efficiency and insecure data storage in centralized institutions.

The fields of use of blockchain include digital currency, certificates, finance, anti-counterfeiting and traceability, privacy protection, supply chain, entertainment, etc. With the popularity of blockchain and Bitcoin, many related top domain names have been registered. It has had a relatively large impact on the domain name industry.

Related Q&A: Can you explain to me what a blockchain is in an easy-to-understand way?

Er Gazi is my childhood friend, and we had our bare buttocks together when we were young._Friendship in Hegou. Later, I came to the city to study and work, and lived a life as a drifter in the north; he farmed at home and did some small business, and now he has a son and a daughter, and his life is safe. He envied my so-called "seen the world", and I envied his simple life without the pressure of mortgage loans. We have completely different and mutually enviable lives??

That day, Gazi came to me on WeChat and asked "District" What is a blockchain?" I was stunned for a moment, how could this idiot care about such an avant-garde word? I pretended to be calm and prepared to talk about the technical principles bit by bit, but I could see the confused expression of that idiot through the screen of my mobile phone. How to explain "what is blockchain" to people who have a little bit of Internet concepts and technical foundation? This seems to be a very thorny problem??

The village commissary interprets the core of blockchain (picture quoted from the Internet)

The core essence of blockchain is "decentralization", and almost all operating modes of blockchain operate around the concept of "decentralization". Once you understand what "decentralization" is, you can basically explain the question "what is a blockchain?" For Erga, of course, he must perform a version that he can understand.

“I said, Gazi, are you still open that canteen at the east end of the village?” Gazi answered yes. I decided to use this canteen as an example to explain the actual use of blockchain in modern business and financial models. Scenario, so that he can better understand what blockchain is.

"Are there still many villagers who take credit now? By the end of the year, some of the accounts cannot be remembered clearly, and there are still many defaulters or those who refuse to accept their accounts?" At this point, Ergazi got emotional and kept complaining. Nowadays, people's hearts are not as old as before, and business is difficult to do!

"In the past, the operation model of your canteen was a typical centralized one. You granted credit to the villagers and allowed them to take accounts on credit. All accounting was done directly through you and our villagers. You were the center of all accounting affairs." Ergazi said I understand, let me continue.

I said: "If you fail one day, then all the accounts will become dead debts? It will be difficult to get back the IOUs written in black and white, let alone those who remember the accounts verbally, but the block The decentralization of the chain can solve this problem very well. As long as the earth still exists, the blockchain will remember that every account will exist forever." Erga became more energetic after hearing this.

The essence of blockchain is "decentralization"

"The essence of blockchain is decentralization. Once someone takes credit from you, all the neighbors in the village will help you keep accounts. Because of the accounting There are many nodes, and it is neither easy to make mistakes nor others to default on the debt, so everyone reaches a consensus. If someone maliciously fails to pay back the debt, the whole village will know his character, and no one will be willing to have financial transactions with him in the future? ?”

At this point, Gazi was obviously a little excited. It seemed that he was really worried about the credit issue. Seeing that Gazi was interested, I felt a little sense of accomplishment and continued: "Of course, the above is just an analogy. In fact, the blockchain does not really allow the villagers to get paper and pen to help you keep accounts, but through the Internet It was completed by networking with the computer."

At this time, Gazi was a little confused and asked:"Then everyone in the village knows what others bought from me. Then who would buy from me? There is really no privacy at all. And you don't have time to keep accounts here. Last year's accounts are said to be It’s this year, what’s the deal with keeping procrastinating?”

“Okay, Gazi, you got the point right with your question.” It seems that Gazi is not stupid at all, and he is still very shrewd in doing business. I continued to explain: "So, the recording and transmission of this information are all done through encryption. What you see is a string of numbers and English, and each account has a timestamp to record the time it occurred. , can't be relied on."

Gazi had another question: "Could it be that the people who owe the debt have a good relationship with the villagers, and they join forces to tamper with the accounting? Then it will be unclear what to say? ?”

“Gazi, that’s all you have to be careful about, haha.” I understood Gazi’s concerns and continued to explain: “The mechanism of the blockchain requires more than 51% of people to agree to tamper with a bill. Yes. There is a degree of closeness and distance between people, and it is impossible for everyone to prefer one person. If it were a computer, more than half of the computers in the entire network would need to recalculate. This project is so huge that it is almost impossible to complete?? "

In this way, through the actual situation of the canteen and combined with some scenes in life, Gazi understood what is in the blockchain: decentralization, distributed accounting, consensus mechanism, encryption mechanism, timestamp, and Characteristics that are not easily tampered with.

Ergazi was silent for a moment, as if he was digesting the example I just gave him, and I don’t know how much he can understand it. Not long after, he sent me another voice message on WeChat: "What does blockchain mean? In the past, when I bought goods online and paid for them, I had to go through Jack Ma's house. If there is a blockchain, can it be done directly?" When trading with sellers, bookkeeping is very safe anyway."

"Okay, Gazi, it's really clear. Blockchain is essentially a decentralized distributed ledger data cloud. Of course, it can be understood as you understand it. "." I am very happy that Ga Zi can roughly appreciate the true charm of blockchain. Fortunately, my words have not been in vain.

What is Bitcoin? (Picture quoted from the Internet)

"Then what is Bitcoin? What does it have to do with the blockchain?" Gazi asked.

I thought about it briefly and decided to continue explaining the story of the canteen to Gazi: "In your canteen, the villagers can't keep accounts for you for free all day long. Do you have to bring something to visit during the holidays? Yes, this is the reward mechanism of the blockchain, and everyone who participates in bookkeeping may receive rewards."

"Then what are the rewards based on? There must be a rule, right?" Gazi asked very puzzled.

I explained: "Zhang San went to your store to buy a pack of cigarettes on credit, but Li Si knew about it first and kept an account for you first. Then other people knew about it and started keeping accounts. Then Li Si could get A small red flower as a reward ~ This little red flower is generated by the blockchain system and has no value in itself, so you do not need to pay any cost for this little red flower??"

"Then Bitcoin can be used as money Flower?How is it different from the banknotes we usually spend? "Gazi continued to ask.

"Bitcoin is a digital encrypted virtual currency. In principle, it has no value itself like our banknotes. However, banknotes have a credit guarantee from the state, so they have value. Bitcoin is the value formed by consensus among Bitcoin network users, and it has tradable properties, so it can be used to carry value. "What is said here is a bit profound. I don't know if Gazi can understand it.

I continued to explain: "Banknotes can be printed infinitely. If more are printed, inflation will occur. When we were young, popsicles worth 1 cent were very good. , now you can’t eat with 1 yuan. Of course, there are many factors that affect inflation. The number of Bitcoins is fixed, and there is no possibility of unlimited over-issuance. However, different people have different judgments on their value, and coupled with the influence of supply and demand and investor sentiment, their prices are always fluctuating. ”

What is the difference between Bitcoin price fluctuations and stocks?

“So is speculating in Bitcoin just like speculating in stocks? Can you understand it this way? "Gazi seems to know a lot.

"In fact, there are some similarities, but there are also big differences. "I continued Gazi's topic: "The price of stocks always fluctuates around the valuation of companies, and there is government supervision in the stock market. Bitcoin itself has no value. It is priced entirely based on supply and demand and player valuations. It grows wildly without any government supervision. Therefore, it may have higher risks and higher returns than stocks. "

In the end, Gazi revealed the real purpose of today. He asked me: "Can I invest in blockchain projects? "

Gazi is a typical example of those who don't go to the Three Treasures Hall for anything. Although there is a large circle of people who are involved in both blockchain and Bitcoin, in fact, what he really cares about is "blockchain project investment" Is it reliable? "When these words came out, I was extremely shocked. Now the so-called blockchain investment projects have actually reached fourth- and sixth-tier cities and small towns!

As of now, there are only three types of blockchain investments. Situation: Mining, currency speculation, so-called blockchain projects.

Mining and currency speculation are still the main lines of the blockchain (pictures quoted from the Internet)

The so-called mining means mining by purchasing mining machines, etc. Equipment, mine virtual currency, and then sell it for cash to get returns. You can install the mining machine yourself, or you can find a mining pool to host it, but the core keys to profitability are "computing power" and "power consumption" as well as Investment in equipment. With the sharp drop in the price of virtual currencies and the increase in mining difficulty, the current mining returns of many currencies are very unsatisfactory. Mining is obviously only a very small number of investors who understand technology can play successfully. I My childhood friend Gazi obviously can’t play with it.

As for “coin speculation”, I have just introduced some differences between Bitcoin and stocks in the previous section. In principle, although they are both “buy low and sell high” operations , but there is a huge difference. Ordinary investors cannot determine the value of a virtual currency itself, and the price is determined entirely by the relationship between supply and demand, which is somewhat similar to what we often call "market makers." On the other hand,The virtual currency trading market is extremely irregular, and fraud and hacker attacks often occur. The risk factor is much greater than investing in stocks. For the safety of my friends' funds, I am one of the ten thousand people who disagree with me and come to "speculate in coins"!

The "September Fourth Movement" stipulated that the issuance of virtual currencies is illegal

In fact, in my opinion, most of the so-called investment projects in the market are essentially "illegal fund-raising" and "pyramid schemes." Some so-called blockchain investment projects attract investors into the circle through various packaging and inflammatory rhetoric, and then create the illusion of profitability by building a software and hardware ecosystem of issuing new coins + mining + currency speculation, and then finally run away. Our country's laws clearly stipulate that the issuance of virtual currencies is illegal.

Illegal pyramid schemes now wear the cloak of blockchain (picture quoted from the Internet)

And how to identify some pyramid schemes under the guise of blockchain? In fact, these pyramid schemes are also so-called Ponzi schemes, what we people often call "empty gloves." These so-called "direct sales" or "marketing" activities often have no actual products to circulate, and rely more on developing "downline" to ensure top-level profits. With the rise of the concept of blockchain, this MLM model has shown an intensification trend, and it even deceives people under the banner of state support for new technologies.

When Gazi asked, “Can blockchain projects be invested in?”, I realized the seriousness of the problem. Gazi is a typical young man from a small town, and his pursuit is his wife and children. But when faced with the attraction of "wealth", people often do inappropriate things. Mining and currency speculation are simply not suitable for him, let alone blockchain investment projects that are most likely "illegal financing" or "illegal pyramid schemes"!

I quickly called Gazi and conducted the above analysis carefully??

⑦ How to define blockchain and what are the application scenarios of blockchain

Now Many people think that blockchain is a universal technology that can do anything. This is a bit of a myth about blockchain technology!
Regarding the definition of blockchain technology, American scholar Melanie Swann defined blockchain technology as an open, transparent and decentralized technology in her book "Blockchain: A New Economic Blueprint and Introduction" database.

Definition of Blockchain: Narrow VS Broad

As for the application scenarios of blockchain technology, it is natural to combine the differences between blockchain and other technologies. In terms of system characteristics.

Blockchain technology features include:

Blockchain is a global A database storage system that can be operated collaboratively in various places is different from traditional database operations where read and write permissions are in the hands of a company or a centralized authority (a characteristic of centralization). Blockchain believes that anyone with the ability to set up a server can participate. Nuggets from all over the world have deployed their own servers locally and connectedConnect to the blockchain network and become a node in this distributed database storage system; once added, the node enjoys exactly the same rights and obligations as all other nodes (decentralized and distributed characteristics).

At the same time, people who provide services on the blockchain can perform read and write operations on any node in the system. In the end, all nodes around the world will complete the process again and again according to a certain mechanism. Synchronize in sequence to achieve complete consistency of data in all nodes in the blockchain network.

At the beginning of this year, the term blockchain began to enter everyone’s lives. From national leaders to aunts who dance square dances, everyone knows this term. This term is widely known by Bit Brought by coins.

As we all know, the first few dozen bitcoins could only be exchanged for one pizza. At its peak, it was more than 20,000 US dollars each, which has skyrocketed by more than a thousand times, which has also benefited a large number of wealthy people. Currently, there are blockchain The virtual currency generated by technology is gradually entering into everyone's life, and many people have joined the ranks of currency speculation. I often hear people say that if you buy the right currency a hundred times, a bicycle will become a sports car, and one coin will turn a young model. You can imagine how many of them are involved. Attractive.

Since 2008, various games applying blockchain technology have also become popular, such as development games (Network Letts Dog, 360 Block Cat), mining games (NetEase Planet, Virtual Earth, Gongxinbao), these are attracting everyone to join in the name of blockchain, and of course there are some that are really reliable, which requires everyone to identify them carefully.

The three words "blockchain" were completely ignited during the Spring Festival that just passed, and the limelight overshadowed everything else. Some people said that this was the arrival of a new era, and the past has become classic, while others said To say that everything is hype is ultimately a bubble.

In fact, blockchain technology is not a new concept. It has been applied to many industries, such as electronic signatures, as early as the past two years. Recently, the third-party electronic signature platform eShanbao revealed the latest progress of blockchain applications to NewSeed.

Currently, blockchain technology is mainly used in e-signing products for certificate deposit and certificate issuance. The application scenarios include copyright protection and online signing. , web page forensics, phone recording, email storage of evidence, etc.

Take the rights protection of online works as an example. Since online rights protection generally adopts the method of collecting evidence after the fact, real-time confirmation of rights is not carried out in the process of evidence generation, so the entire confirmation process is difficult. The copyright process is time-consuming, difficult and costly to obtain evidence, and extremely difficult to prove and trace the source. It cannot meet the characteristics of rapid dissemination and large quantity of online works.

eShanbao's new intellectual property protection solution based on timestamp + blockchain starts from the user's real-name authentication and solidifies the process in real time.The electronic data generated in the network are stamped with legally valid timestamps on online works through the time source service synchronized with the National Time Service Center, proving that the electronic files have not been tampered with in a certain period of time. Blockchain technology can establish point-to-point trust in the network, ensuring that all blockchain nodes can record complete copyright confirmation and transaction records, and can trace their origins, truly realizing anti-repudiation and anti-tampering, and realizing a kind of distribution. trust infrastructure.

Founder and CEO Jin Hongzhou believes that the application of decentralized blockchain technology has greatly improved the efficiency of data storage and certification, and The credibility of the identity of the parties reduces the cost of trust, but it cannot replace the original centralized public key encryption technology. The two should complement each other. Through the combination of the two, it can provide users with real-time and reliable Confirmation plan.

Next, e-Shanbao will also focus on building a smart contract platform based on blockchain technology. Jin Hongzhou said that data storage, Issuing certificates is only a relatively superficial application based on blockchain technology. It is the first step to implement blockchain technology, and the realization of real smart contracts is the second step. "Smart contracts cannot simply be understood as electronic contracts. They refer to a process, from the conclusion of the contract to the confirmation to the final execution." Jin Hongzhou explained.

Through the following limited cases, I hope everyone can understand the actual performance of blockchain technology, thereby stimulating interest in such solutions.

1. Administrative Services

Over the centuries, the roles and responsibilities of public administration have not changed significantly – or rather, what has changed dramatically is actually the size of the data and the specific ways in which public agencies handle it. Although various digital technologies already exist to help collect and process data, issues such as anonymization, portability, and the immutability of large amounts of data remain unresolved.

Sasha Ivanov, founder, entrepreneur and CEO of Waves Platform and Vostok projects, said, "What the public administration currently lacks is a more convenient user experience (UX) for data use. To improve the user experience , we should introduce some kind of layer to it that acts as a trusted public environment that is transparent and can store data anonymously and immutably."

Governments are working on this by launching the U.S. Federal agency and enterprise-level initiatives such as the Federal Blockchain Initiative are gradually confronting the existence of such problems. The United States held its first federal government blockchain forum in July 2017, and the U.S. General Services Administration currently has more than 200 related use case repositories. Ivanov explained, “Distributed systems can really help us establish such a reliable environment, improve our big data work, and evenBringing all emerging technologies together—including artificial intelligence, the Internet of Things, and more. In fact, whenever we face any kind of technology, it always embodies the sum of other technologies. ”

Now, the system supported by the blockchain can actually work - this view has been unanimously recognized by all experts and has become the most important theoretical basis. In other words, next we have to What we do is to create more production-ready solutions.

2. Payment services

The government needs to process transactions, many of which involve the exchange of funds with citizens. District Blockchain technology has huge potential application value in reducing the cost of fund transfers - including using new blockchain-based cryptocurrencies as intermediate transaction carriers, or using blockchain as a means of fund transfer, etc. Once a perfect solution is found , the business opportunities contained therein will be endless - especially for those who need to conduct frequent cross-border or Internet transactions.

The Jasper project was developed by the Bank of Canada to help it further think about central banks And how other financial institutions should implement payment operations between different banks based on distributed ledgers. The Bank of Canada has also developed its own digital currency variant "CAD Coin" to test the use of a certain national currency on top of the blockchain The feasibility of it.

This project brings an interesting conclusion, that is, we should say no to the proof-of-work public chain system. In an article titled "Jasper Project: Is a distributed batch payment system feasible?" "In the paper, the author observed that "Proof-of-work systems are not suitable for such large transaction processing systems because they assume that all transactions in the system require publicity and observability to a certain extent. ”

3. Digitization and Intellectual Property

The government is responsible for maintaining copyright records and databases. These records prove the ownership of intellectual property. A blockchain-based system allows various artists, Performers and writers can time-stamp their works and theoretically detect copyright infringements and even retain permanent records of rights. In fact, many governments have taken important exploratory steps in this direction.

Iran recently announced that it will deploy this technology. "Iran Financial Tribune" quoted Morteza Mousavian as saying that "the Digital Media Department of the Ministry of Culture has reached an agreement with a blockchain company to jointly design a usable A system for protecting online copyright. "He also added, "Relevant programs will soon be released to users in an easy-to-use manner. ”

This work is still in the early stages of exploration, but it provides corporate customers with the possibility of preserving records through replication technology. From a theoretical level, companies can use blockchain solutions for financial accounting, And discover errors in real time.

4. Welfare distribution

The government has the responsibility to create a level playing field for citizens. Citizens who are chronically poor or economically disadvantaged certainly need government support and assistance to ensure that they are able to sustain themselves and develop. However, welfare distribution is neither simple nor often straightforward. Problems such as corruption and impersonation have been wreaking havoc on various distribution channels within government schemes.

In China, the National Council of Social Security Fund is conducting early research on how to use blockchain technology to improve the delivery of national benefits to citizens. At the same time, India is also taking action. Andhra Pradesh and Telangana are already using blockchain to support their civilian resource supply systems.

It is said that many companies, including Microsoft, are also considering using the same technology. These solutions, which will touch individual employees and functional roles, are expected to gradually appear in small businesses in the near future.

5. Bidding activities

In order to build public infrastructure or provide related services, the government hopes to achieve economies of scale and competitive gains through bidding as much as possible. However, the bidding process is often not fair or transparent. Public procurement has long been a major scene of rampant corruption around the world. Transparency International noted that “many governments will award project contracts to a certain supplier in the absence of fair competition. This allows companies with greater political resources to improperly win over competitors; or companies in the same industry Bids will be negotiated in advance between companies, ensuring that each company gets a share of the tender. This will significantly increase the cost of delivering services to the public - we have found that corruption issues can increase project costs by 50%."

So, how can blockchain technology solve the bidding problem? According to Ivanov, “Unlike decentralized centralized systems, independent ledgers powered by blockchain will be able to improve bidding or anything else that needs to be tracked. Transparency of financial processes. The intervention of blockchain technology will help track the use of funds and ensure that they are paid out as expected and within the allowed time."

Currently, Japan's internal affairs and The Ministry of Communications has announced a blockchain-based bidding system, which means that in industries with serious collusion problems, small and medium-sized enterprises are expected to usher in a more transparent bidding method and brighter development prospects.

Although quite a few of the cases mentioned previously are far from finalized, they do provide many possibilities for companies and governments. Of course, the key lies in implementation; and we should also look at all this with optimism, that is, although blockchain technology is often misunderstood, it is and will eventually find a direction in which it can exert its own energy!

< p> In layman's terms, the blockchain is like a dozen beacon towers on the Great Wall. If an enemy comes at one place, they will set off smoke. The other beacon towers will know about it and enter together.defensive status. In technical language, it is a distributed ledger. Each node keeps accounts separately. The failure of one or two nodes will not affect the entire network.

How is this distributed network different from the distributed servers of Google Network? Google Network's distributed servers still belong to Google Network and are controlled by their central scheduling algorithm. The distributed nodes in the blockchain do not know each other and have no legal relationship. You can just go offline and shut down if you want, but because of the currency rewards, there will always be someone who will turn on the machine as a new node to support the network.

After the popular and technical explanation, I hope you understand. So the first application scenario is finance. I put my money in Alipay. If Alipay doesn't recognize it one day, there's nothing you can do. But on the blockchain, it is useless if one node does not acknowledge it, because other nodes still have my records. The second is the contract. Nowadays, contracts are made on paper and are easy to be faked. But if they are put on the blockchain, they cannot be faked.

There are more application scenarios. It is recommended to check the top 100 digital Huobi online to understand the corresponding projects behind them and become a blockchain expert. .

Blockchain technology was first used in Bitcoin. Blockchain provides a reliable and trustworthy means of organizing data for cross-subject business scenarios. JD.com is essentially a supply chain company, and blockchain technology will be first used in many scenarios of the supply chain.

Blockchain is a decentralized technology. Blockchain can be applied to all products currently covered by the Internet.

The most popular application industry at present is the financial industry.

An application that has been implemented is product traceability. Alibaba and JD.com are already using blockchain technology to fully trace the origin of some of the products they sell. Consumers can trace the origin of the purchased products. There are also many blockchain applications in the digital advertising industry. Since digital advertising traffic fraud causes losses of tens of billions of dollars every year, there are already blockchain application projects based on digital advertising, such as DCAD, which is based on blockchain. The digital advertising application of blockchain technology mainly solves the problem of traffic fraud

In the future, as the application of blockchain technology becomes more mature, it will be applied in many industries, creating a new ecosystem based on technological trust. Mode

The characteristics of blockchain are distributed accounting and decentralization, but the ultimate goal is to make people get along more equally. Technology is meaningful only when it serves human values, and technology that meets human value needs will develop. Therefore, blockchain is in line with human pursuit of freedom and equality, so its trend to become mainstream is unstoppable.

Currently, there are many blockchain gimmicks, which are basically used for issuingcurrency. The newly launched ono is a decentralized, free and global social platform. Due to decentralization, your chat communication information is peer-to-peer and cannot be viewed by others. In other words, your every word and deed will no longer be recorded and reviewed at any time like it is now on WeChat, QQ, and Facebook, freeing you from the trouble of surveillance.

In fact, blockchain technology can be used in any field. Information that previously required third-party confirmation can be completed online and confirmed at multiple nodes, making it difficult (almost impossible) to delete.

At present, blockchain is still in its infancy, and the technology is not mature enough, but it is also a better time to enter.

What is blockchain

If you use non-technical terms to explain blockchain, blockchain is a place where data is stored. However, the data stored in the blockchain is safe and reliable and does not need to be managed by anyone, so In the Internet, a place where data and information are exploding, having such a place would be like a magical treasure.

What can the blockchain do?

If you ask what the blockchain can do, it is better to say what applications require the use of the blockchain. As mentioned earlier, blockchain is a safe place, so wherever data needs to be protected securely on the Internet, blockchain technology needs to be used. For example:

Because the use of blockchain technology can better protect the data of policyholders, in today’s Internet, data is value and wealth, so value protection and value transmission are the future development directions of the Internet. And blockchain technology can really do just that.

If there are any deficiencies, you are welcome to comment and correct me.

In a narrow sense, blockchain is a chained data structure that combines data blocks in a sequential manner in chronological order, and is cryptographically guaranteed to be non-tamperable and non-tamperable. Fake distributed ledger.

The two parties involved in the transaction do not need to know who the other party is, nor do they need a third party for trust endorsement. They only need to trust a common algorithm to establish mutual trust and conduct direct transactions.

Its characteristics are trustlessness and decentralization. The destruction of each node's ledger has no impact on the entire blockchain. The blockchain runs point-to-point payments without a center that may cheat, and the security is greatly improved. Improved, the entire transaction network has changed from a star structure to a point-to-point P2P structure.

In the future, blockchain will be used in many fields and will have a great impact on human life. . It can be widely used in fields ranging from digital currency to securities and financial contracts, medical care, games, artificial intelligence, smart contracts, Internet of Things, e-commerce, file storage and other fields.

1. Cloud storage

This is the statistics of current cloud storage on the Internet.Google has the largest amount of data, which is 8,000PB. So what if we share the idle data on the Internet?

Starlight Cloud builds a blockchain data computing and storage lake through Starlight Chain, with a total storage capacity of 15,000P (approximately 15.72864 billion G) in the future. This will be more than 10 times that of Alibaba Cloud's 1500PB! It is also more than four times the size of the Taizhou Storage Center, the largest storage lake in the world after expansion.

2. Medical aspects

Using blockchain technology to save personal medical records also retains personal medical historical data, which can be used when seeing a doctor or planning for your own health in the future. Historical data can be called directly. These data are highly private, and the use of blockchain technology also helps protect patient privacy.

⑧ How to introduce blockchain in 3 minutes in a simple and easy-to-understand manner, and what its commercial value will be in the future

There is a real joke, Ant Financial I served an engineer. He wrote a blind date resume. The job description in it was "code farmer", but no one clicked it for a long time. Later, he changed his work experience to "blockchain" and received it all at once. 381 letters of love.

From workers in high-tech industries to square dancing aunties, it seems that everyone is participating in the blockchain carnival. So what exactly is the seemingly mysterious blockchain? After reading the following content, you will have completed the journey from beginner to beginner.

1. What is blockchain?

To put it bluntly, the blockchain is "everyone keeps accounts together." Any database needs a big housekeeper to be responsible for "accounting" (maintaining the system and entering data). But after using blockchain technology, the concept of this "central steward" disappears, and each of us can participate in accounting. So the question is, whose record will ultimately prevail? Of course, it is the person who completes the work well and quickly. A system that strictly adheres to fairness will select this person based on the algorithm, write the contents of his records into the ledger, and send the contents of the ledger during this period to everyone in the system. of others to perform backups.

2. What is so powerful about blockchain technology?

Any new thing must have unique advantages if it wants to develop rapidly, and the same is true for blockchain technology. First of all, blockchain technology ensures the security of the system. In the absence of a central steward, everyone is a defender of the home, which means that destroying some nodes has no impact on the system at all. Second, the recording process cannot be cheated. In the blockchain systemEveryone has the same ledger and the entire process is open and transparent. The system will determine the final result based on the opinions of the majority. It is difficult for an individual to hack into so many computers at the same time, and it is meaningless to just modify one's own results. Who would do such a thankless task? Third, and most importantly, the blockchain completely abandons the existence of "credit intermediaries". Credit intermediaries are the platforms we must pass through when transferring money, such as traditional banks. Now any two strangers can directly complete mutual trust transfers, and the efficiency has been improved not only a little!

3. What is the use of blockchain technology? ?

As mentioned above, the main advantages of blockchain are that it does not require intermediary participation, the process is efficient and transparent, the cost is very low, and the data is highly secure. That is to say, any industry that has needs in these three aspects can use blockchain technology. Here are a few examples:

In the banking industry, the use of blockchain technology is equivalent to updating a digital, secure and tamper-proof General ledger books. In fact, Swiss bank UBS and Barclays Bank in the UK have already begun experiments, hoping to use it as a way to accelerate back-end system functions and clearing and settlement capabilities. Some institutions in the banking industry claim that blockchain may reduce middleman costs by 20 billion.

In terms of car rental, blockchain also has great potential. A future customer selects the car they want to lease, entering it into the blockchain's public ledger; then, sitting in the driver's seat, the customer signs the lease agreement and insurance policy, while the blockchain updates the information simultaneously. This is a foreseeable future for car sales and car registrations.

In terms of medical and health care, blockchain technology allows hospitals, patients and all parties in the medical benefit chain to share data in the blockchain network, and Don’t worry about data security and integrity. This means more accurate diagnosis, more effective treatment, and an improvement in the health system’s overall ability to deliver cost-effective care.

Blockchain is not cold-blooded. It has been implemented in applications that are closely related to our lives. For example, the application of Ant blockchain ranges from public welfare, to mutual insurance, to traceability of product authenticity, to traceability of rental housing.

In 2018, blockchain will "return to the world."

Blockchain, do you really understand it? Since it says three minutes, let’s give a simple answer.

1. What is blockchain;

2. What are the benefits of blockchain;

3. What are the uses of blockchain;

< p> 4. Blockchain technology and existing problems;

Let’s first look at the first question: What is blockchain

Let’s look at it literally, blockchain Chain is called Blockchain in English. This is a very good word. The English name is well chosen and the Chinese translation is also very beautiful.

1. What is a "block"?

You can think of it as a record, or anything, which forms such a record during the production stage. This thing can be any physical or virtual object in the Internet of Everything.

For example, if you generate a Bitcoin, which is a thing, it actually corresponds to a block. This block is a record of what it is.

When you produce a bottle of medicine in the future, a block is actually generated when this bottle of medicine is produced. When it leaves the factory, it needs to be recorded once, and this corresponds to it one-to-one.

This is the first dimension.

To make it easier to understand, for example, each of us is born with a unique identifier, which is our DNA. All species in the world have different DNA. Every individual's DNA is different.

Your parents can name you Zhang San, Li Si, Wang Wu. These names can be repeated, just like a bottle of medicine, whether it is aspirin or penicillin, these can also be repeated. famous. However, human DNA is different. Even if you have identical brothers and sisters, your DNA is different, so this is your unique identifier. And once your DNA is formed, it cannot be changed. This is a benefit of the blockchain.

2. What is a "chain"? The chain is actually a process. You can think of it as a transaction process. After this bottle of medicine leaves the factory, it enters the warehouse from the workshop and passes through a certain door, and it will record the process.

Of course, this requires automatic computer recording, and the cost of human recording is too high. Then, packing is a process, and transportation to the cargo transfer station is another process. Then it is loaded into a car and transported to the wholesale station, which is the next process.

Every step of the process is recorded. It is a process to go from the wholesale station to the store, it is another process for the people in the store to receive this batch of medicines and put them on the shelves, and it is still a process for you to buy them. Finally, when the whole process is connected, you will have a way to track the entire process of this bottle of medicine and know its authenticity, because once this bottle of medicine is produced, it will be bound to the blockchain, as well as to people and people. The same is true for DNA binding, which cannot be changed, but it can be seen and tested.

Doctors can also determine whether this person is you by testing DNA.. So in terms of nature, if we virtualize it, it is actually a smart contract. You have signed a sales relationship with one of your customers. Once this happens, it cannot be changed. Then everyone can only execute it. This execution process is the same as the tracking of drugs I just talked about.

Second question: What are the benefits of blockchain?

1. Mathematically speaking, it is very beautiful. It changes from the past that you had to own something before you could know its properties to that you don’t own it, but you can ask questions Learned many details about it.

Mathematically speaking, this is a perfect asymmetric situation. You can tell whether it's true or false, but you can't change it.

2. Theoretically speaking, blockchain is very safe. For example, if you participate in the process of a bottle of medicine, others cannot see this information. That is to say When you buy this bottle of medicine, you can know where it comes from, but others cannot.

For the same reason, for example, if we sign a contract, others can verify the contract. If you go to a bank for a loan, he can ask you the amount.

However, he cannot obtain this contract, and he cannot steal this contract from your computer.

Blockchain also has some very interesting properties. For example, a block chain can be divided into two at will, or several can be combined into one, etc.

3. Blockchain is transparent, which means that everyone abides by this algorithm and there is no special agreement in private. So, if you believe in this algorithm, it means you believe in me and believe that I didn't do anything fishy. I will not secretly do anything in the contract to make you suffer losses.

This is a beautiful place theoretically and mathematically.

In the third block, let’s take a look at the uses of blockchain

1. Bitcoin is a cryptocurrency, and the Ethereum currency that everyone uses now is also a cryptocurrency. Of course, you can make another one based on it, either Zhang three coins or Li four coins. As for whether it can replace the currency of the future, this is doubtful.

2. Financing, we used to divide financing into three stages: the first stage is to get a loan from the bank. If you want to open a restaurant, you need to mortgage something. The second stage is that you issue some stocks and I sell 10% of the stocks, so that I can obtain part of the funds.

The third stage is actually crowdfunding. For example, if I want to write a book, it may cost 50,000 yuan for the publishing house to publish it. If any of you can give me 50 yuan at the beginning, I will use it in the future. Once the book is written, give everyone a copy. You will get the book, and of course I will publish it. But there is a problem. For example, if I sell this book for 100 yuan and you get it for 50 yuan, what if my book sells well?I bought 100,000 copies, but you don’t seem to have benefited from me. What should I do?

Is there a fairer way to measure everyone's contribution? One way is to issue a cryptocurrency (ICO). When the business we do becomes bigger in the future, you can benefit from it.

3. Smart contract, for example, sign a contract. In the future, the smart contract can become like this. All the nodes in the middle are determined when the contract is signed, such as building or decorating a house for you. , your payment must be given to me at any stage of the decoration. If you accept it, no problem, the payment will be automatically given to me.

You can even sign with my supplier, which means that as soon as my money arrives in my account, I will give it to my supplier immediately. This will eliminate many triangular debt problems in the future, including the problem of arrears to migrant workers.

Blockchain can also be used for property registration, car registration, etc. Of course, another great use is gambling. In fact, gambling is the most willing to adopt new technologies because it is closely related to money.

After talking about the benefits of blockchain, let’s take a look at the technology and existing problems of blockchain.

Today’s blockchain is basically the second generation and the first generation. It is the Bitcoin generation. It has many problems. It is not a platform, but is actually a specific application.

The second generation is represented by Ethereum. It is a platform on which you can issue your own coins, and it removes the concept of mining machines, so its transaction costs will be much lower. . The reason why ICOs are everywhere today is because with Ethereum, you can issue coins. Unlike in the past with Bitcoin, you had to completely copy its formula and copy it again. Today you are on Ethereum. , it is easy to issue your own currency, just like you can easily make your App on the Android operating system today.

There are three problems with Bitcoin transactions

1. The transaction delay is very long. I asked people who specialize in Bitcoin transactions and the delivery time ranges from two hours to two hours. Days wait, so it is very inconvenient for you to use it to launder money. After the RMB is converted into US dollars, it may fall by 20% in two days, and you will lose 20% of your money.

2. It cannot be distributed. Like Bitcoin, the early people took away a lot of its shares, so how to distribute it in the future is also a problem. No one knows clearly, so it is difficult to use it as a currency. a currency. Because if it really becomes a currency that everyone uses, it will be equivalent to the first few people taking away a large part of the world's property.

3. Transaction costs are high. For example, a cup of coffee at Starbucks in the United States costs $2.50 on average. You usually pay money at the counter, and the transaction time is only one minute. If you want to use Bitcoin, you have to wait two hours before you can get coffee, and the transaction costs are extremely high.The electricity bill is $20. In other words, if you pay $2.50 for coffee, the transaction cost of electricity is $20, so this is unrealistic.

Blockchain has high risks. This risk is not only a technical risk, but also a policy risk. In fact, this is also an opportunity. Whoever solves this problem will get the opportunity. Its transaction costs are also very high, so whoever can develop new underlying technologies and reduce this transaction cost will make a lot of profits in the future.

Some people say it is the next generation of the Internet. I don’t agree with this, but it will definitely be a supplement to the Internet. Some people say whether it can subvert the central bank, but this is not certain, because there is no reason why the central bank or these big banks cannot do this themselves, so those who expect it to subvert the central bank may be too happy too early.

Perhaps in the end it was these large financial institutions in the past that used the blockchain to update themselves.

Talk in the vernacular and get useful information!

Literally, blockchain is blocks and chains, and some relationship between them. It is essentially a distributed accounting method and a network database system that cannot be tampered with.

The current development directions include digital currency, payment, smart contracts, defi finance, web3 and so on. It is still in the initial stage of development and is a back-end technology. Most projects are still speculating and financing.

Today’s Afghanistan may best prove the value of Bitcoin, and there is no problem with value storage

Blockchain is not just a technology, it is a way of trust transfer, value The way it is delivered may have huge potential in the future.

Keywords: block, chain, database, ledger, Afghanistan, currency speculation, value, technology, market

First, what is a blockchain? Blocks and chains are an accounting method and a form of network data storage.

Literally speaking, blockchain refers to blocks and chains. This block actually records the transaction records of the entire network, or the execution result data of smart contracts, etc.

Every once in a while, the entire network will produce a block. This block records all transfer data, and the blocks need to be connected by some kind of "chain".

This chain is an encryption algorithm. Some information of the previous block is used to calculate and obtain certain information of the next block. They are linked together. The latter block can trace back to the previous block and needs to be modified. The next block must modify the previous block, all the way to the first block. Regarding the details of these issues, I have written many articles before. If you are interested, you can go back and take a look.

Blockchain is actually an accounting method, or a database storage method. Please pay attention to what I say below. The whole process is the operating mechanism of blockchain.

Each node in the entire network has the same status, run the same program. This program is used to collect, encapsulate and package all transaction record data records that occurred in the entire network within a period of time. Then broadcast it to the entire network

Let’s take Bitcoin as an example. Once this packaging and encapsulation is completed, you can obtain the right to produce the block. A certain amount of Bitcoin can be issued every time a block is produced. Since the nodes in the entire network run the same program, there is no center to control everyone. Therefore, the currency issued is irrevocable and cannot be changed.

How to decide who has the right to make a block? This requires the use of the so-called consensus mechanism, which is to establish a rule and use who produces the block as the benchmark to solve the problem of network consistency. The mainstream consensus mechanisms include POW mechanism and POS mechanism. Proof of work and proof of stake. Proof of work, who does more work, and proof of equity, who stakes more assets

Pow means that everyone calculates a difficult mathematical problem together, whoever calculates it Whoever comes out has the right to produce the block. Pos means that everyone takes out their family assets as mortgage, and whoever mortgages more. It is possible to be selected as a block producing node.

The essence of this approach is that you have to pay a certain price and receive a certificate of investment, which essentially builds a kind of trust.

When all these tasks are completed, a block can be produced, and the block will be connected to the previous block one by one. This is the entire block sequence. Note that the entire blockchain world will produce many blocks, connected to one chain after another, but everyone will only recognize the longest chain, and short chains will be discarded.

To put it simply, each network node uses a program to package transactions within a period of time, and then connects the transaction blocks one after another and saves them in each node, but an encryption algorithm will be used in the process. Ensure that node information is not leaked, ensure that user information is encrypted, and ensure that the information in the block is not hacked or tampered with.

Second, the block The current development of the chain, various projects and significance, at this stage are more about currency speculation, and there is no problem with value storage.

Blockchain has been developing for twelve or three years since the Bitcoin white paper in 2008. It has also experienced various evolutions and developments.

For example, now it has gone from being able to issue currency in a distributed way to now having huge functional expansion. The landmark event is the birth of the Ethereum smart contract.

I have explained many times that a smart contract is an automated contract signed by two or three parties. It will be automatically executed as long as the conditions are met. It is essentially a program with infinite possibilities and the judge in the blockchain world. Various functions can be input into the program, and the program exists. Blockchain has become rich and colorful.

Current blockchain applications mainly include the following aspects:, smart contract class, payment class, cross-chain asset class, oracle class, defi class, web3 storage class, etc. I will briefly give two examples to talk about its commercial applications.

For example, defi applications are quite popular on Ethereum now. Defi is decentralized finance. Abbreviation for decentralized finance.

What does it probably mean? It is to move all financial-related businesses in real life, such as mortgages, insurances, and loans, onto the blockchain.

This field is very popular now, and the reason is simple. It is very suitable for blockchain. As I said, a smart contract on the blockchain is a contract. If the contract conditions are met, execution can be automatically triggered.

In the past, it might have been very troublesome for you to go to the bank to apply for a loan. You had to sign various signatures and verify them, and the bank might not be open on weekends and nights

But with blockchain The network operates 24 hours a day. If you want to run various assets on it and do various mortgage transactions, you only need to click and there is a software terminal.

Of course, the real assets will be frozen in the process and mapped to virtual assets. After the transaction is completed, they will be exchanged for real assets. Cross-chain technology and oracle technology may also be used in this process, which I have written in detail in other articles.

It roughly means cutting off banks through decentralization, and direct point-to-point transactions. The security of transactions is guaranteed by blockchain technology, code and cryptography.

There is also the current web3 storage class. For example, the leading project fil. His vision is to take out all the scattered hard drives. Break all the data and information that need to be stored on the network into small pieces

and then distribute them to the entire network. When we want to use network data in the future, we no longer need large network database or server. In this way, Internet giants cannot charge high service fees. There is no way to maintain a monopoly.

If you want to obtain stored information, just take a taxi online like dd. You pay for a taxi, so that information on the Internet can flow freely. Costs will drop significantly.

Of course, these visions are grand and huge, and the current blockchain development is still in its early stages. There are still some technical difficulties to be overcome and some underlying systems to be established, but there is no problem in this direction.

The original digital asset projects like Bitcoin have now been proven to be very safe. Just like this situation in Afghanistan, the first thing that comes to my mind is Bitcoin. He is the first violent and unplunderable asset.

Your house may be occupied and blown up, and your gold may be robbed. And if you have Bitcoin, it's much easier. He can't snatch this thing away, because the mnemonic phrase and private key are in your mind, and he doesn't even know it.I don’t know if you have this in your mind. If you want to pass it on to your child, just ask him to memorize the key and mnemonic phrase.

It is precisely because we are now in a stage of financing and bubbles that all the news you see on the Internet is still speculation.

Also, this thing is a back-end technology. For example, Guangdong Province already has blockchain invoices. For example, there are already some blockchain apps for judicial certification, but for the front-end For you, you can't feel it. There is an extra string of hash codes on the invoice, can you tell the difference?

This is why when it comes to blockchain now, everyone is speculating on coins, but in fact it has certain applications and future technical logic.

Third, it is essentially a mechanism of trust, a method of value transmission, and an exploration of social governance methods.

What is the essential value of blockchain? The most important thing is that it is a way of credit transfer. Because there is enough credit, real-life assets and property values ​​can be spread on the Internet in the form of information codes.

Mainly in these aspects.

First, before Bitcoin, people did not know how to protect a piece of information, because information on the Internet can actually be copied. Bitcoin solves the problem of uniqueness of information assets. With scarcity, there is value in transactions and storage.

The second is decentralization and disintermediation. We used to do everything. All require some kind of intermediary. For example, when you borrow money, a bank acts as an intermediary, and when you buy a house, various institutions and real estate agencies act as intermediaries.

You cannot buy or sell directly. Because you don't have enough credit. We usually come to find a third party, but the third party is usually made up of people and may also do evil.

For example, the master who could whip five lightning whips a while ago. If he calls you all kinds of names at the beginning, you may be frightened. You won't know he is a liar until he is punched and lying straight there. This is human credit, which is unreliable

Blockchain ensures credit through code, cryptography, and consensus mechanisms. We no longer need a powerful third party. Note that this third party will often become a monopoly boss.

The third is to reduce the cost of coordination, communication and entry barriers.

If we want to become richer, we need to trade in the market. Transactions require coordination and division of labor. Essentially, the companies and organizations we work for are intermediaries.

You have to integrate your resources through this kind of intermediary, transform your labor force, your brainpower, and your ingenuity into final products and sell them on the market.

The smart contract technology of blockchain technology can break up these contracts in a decentralized manner. People in the market can combine freely,Establish a new type of organization that is completely transparent and cannot tamper with the rules, that is, a blockchain autonomous organization. The future of this kind of organization may be more promising than that of ordinary joint-stock companies.

You can join or quit an organization at will, and the trust between you and others has been resolved. You can cooperate with others and sign smart contracts to complete joint collaboration and complete a certain product. We no longer have to worry about some big capitalist taking advantage of everyone and getting the bulk of the profits.

So the Bitcoin blockchain is essentially a big social experiment, through the consensus mechanism, the decentralized decision-making method, and the distributed signing of smart contracts. Gradually and completely change the original appearance of our society. Restore the original ideal of market economy, peer-to-peer, direct transactions between people.

To summarize. Blockchain is a block of information connected together through an encryption algorithm. It is essentially an accounting method and a network data structure

Through decentralization, you can do finance, storage, and decentralize many things, but now it is still very In the initial stage, most projects are still in the stage of speculation, financing and concept development.

The value storage capability of the blockchain has been proven to be problem-free, very safe, and cannot be plundered by violence.

The essence of blockchain solves the problem of credit intermediary, and at the same time can reduce the cost for people to work together, lower the threshold for enterprise entry, improve social efficiency, make social transactions larger, and allow We are richer.

I recommend the book linked below, it is easy to understand. Like You Pump tells the history of the birth of blockchain, the underlying technical logic of blockchain, and some mainstream projects. Learn some knowledge about blockchain, feel more at ease, and no longer worry about whether it is a scam.

⑨ Beginner’s guide to investing in digital currency (blockchain), just read this article

Blockchain and digital currency investment relative to other investments The entry barrier is relatively high. Many friends want to invest in digital currencies but don’t know where to start or what to learn. Although 51coins has updated a lot of relevant knowledge in the "Beginners Playing Coin" section, it is not systematic enough

This time we will systematically organize the information related to blockchain and digital currency investment. In summary, let everyone understand and invest in digital currency faster and more conveniently

1. Understand the blockchain and digital currency

No matter what you invest in, you must understand it. The same goes for blockchain and digital currencies. There are many introductions about blockchain on the Internet, some are too profound, and some are not comprehensive enough. I personally think the video "100 Questions on Blockchain" produced by Huobi is better

100 videos , all are blocksChain-related knowledge, including: the birth of Bitcoin, operating principles, blockchain FAQs, mining, wallet introduction, etc., and are all in the form of animated videos, making it easier for everyone to understand. Although the explanation is not detailed enough, it can give you a preliminary understanding of digital currency and blockchain

2. Choose a trading platform

After understanding digital currency, you can try to use the trading platform Purchase a small amount of digital currency and experience the process. The purchase and sale of digital currencies must be completed through a trading platform, which is equivalent to a stock exchange in the stock market. It is recommended to choose a large trading platform for the trading platform, which has a comprehensive range of currencies, convenient transactions, and guaranteed fund security

The following three platforms are recommended: Binance, Huobi, and OKEX (ranked in no particular order)

< p> 3. Choose a wallet

If digital currency is compared to cash, a wallet is equivalent to a bank card, used to store digital currency. There are many types of wallets, and the most commonly used ones now are mobile APP wallets (light wallets). Wallets are also divided into types. Different similar digital currencies cannot be transferred to the same wallet. For example, if imtoken is an Ethereum wallet, it can only store Ethereum and tokens issued based on Ethereum, but not other currencies

< p> There are also wallets that claim to support all digital currencies, but most of these wallets are not yet complete.

Of course, after we buy digital currency, we don’t need to deposit it into the wallet, but directly put it in the exchange account, which can save the handling fee and not be so troublesome. Large exchanges such as Huobi and OKEX are relatively It is safe. I personally basically put digital currencies on exchanges

4. Determine the investment plan

Before investing in digital currencies, we must first determine our investment plan and plan to invest. How much money, how much loss you can accept, what is the expected return, and how long the investment time frame is, determine it before investing. Digital currency is a high-risk, high-yield investment product. In the novice stage, you can invest only your spare money that does not affect your life. There is no limit on the amount of investment, and the minimum investment is a few hundred yuan.

Wait until you truly understand the market before making the appropriate investment. Increase the investment amount, but remember to keep the investment amount within your tolerance

5. Select the investment currency

After selecting the trading platform and confirming the investment plan, you can purchase Digital currency, so which one should we buy among so many digital currencies? When buying coins for the first time, it is recommended to choose mainstream coins. You can choose a few coins that you like among the top 20 in the market or recognized value coins

Find out what these coins are for and whether they are available. What is the actual value, what news has recently affected the currency price trend, etc.

Understand these issues before buying, and be sure to pay attention to the purchase price before buying

6. Common tools, Website

1. Non-small account: You can view information related to various currencies and exchanges, including currency prices and history.Price, rise and fall, circulation, ranking and other information

2. AICoin: The function is similar to that of non-small accounts. The K-line of aicoin is very convenient and easy to use. It is the first choice for viewing K-line charts

< p> 3. Coin World: Real-time updates of various blockchain and digital currency-related news and information

4. Golden Finance: A relatively comprehensive blockchain media platform, including news, news, quotes, and celebrity columns Wait

7. Learn more relevant knowledge

Even if you have initially learned digital currency investment with the above 6 points as a foundation, we still need to learn more if we want to truly make money by investing in digital currencies. Much knowledge. The two most important points are to deepen the understanding of blockchain and technical analysis (K line)

These two are too broad and cannot be learned overnight, so I will not introduce them, K You can find a lot of online knowledge online. As we invest longer, understand more currencies, and come into contact with more related matters, we will gradually deepen our understanding of blockchain.

⑩ Illustration of what is blockchain< /p>

Blockchain is so popular that it has begun to affect my life. I don’t even want to know about it. Today I will take a look at what blockchain is.

Structure of this article:

As its name suggests,
A blockchain is a chain composed of a set of blocks.
A block is a block of information that contains information. , the chain also contains information.

Blockchain technology was first developed by a group of researchers in 1991 to time-stamp digital documents so that these documents cannot be tampered with. It basically played no other role after that until 2009, when Satoshi Nakamoto used blockchain technology to create the digital cryptocurrency Bitcoin.

A blockchain is a distributed ledger that is completely open to everyone. It has a very interesting property: once certain data is recorded in a blockchain, the data is very It is difficult to change.

Let’s take a look at the composition of a block:

Each block contains some data, the hash value of this block, and the hash value of the previous block. Hope value.

The data saved in the block is related to the type of blockchain. For example, the blocks in the Bitcoin blockchain save relevant transaction information, including sellers, buyers, and transaction Bitcoins. quantity.

Each block contains a hash value. The hash value is used to identify a block and all the content it contains, and it is unique, like a fingerprint. Once a block is created, itsThe hash value is calculated accordingly. If you change something in the block, the hash value will change. If the fingerprint of a block changes, it will no longer be the previous block.

The third element contained in the block is the hash value of the previous block. This element allows links to be formed between blocks and makes the blockchain very secure.

Suppose we have a blockchain containing 3 blocks
Each block contains its own hash value and the hash value of the previous block
No. 3 Block points to block No. 2, and block No. 2 points to block No. 1
Block No. 1 is a bit special, it cannot point to the previous block because it is the first
We put 1 The block number is called the genesis block.

Now suppose we tamper with the second block
This will cause the hash value of the second block to change
This will then cause block 3 and 3 All subsequent blocks connected to the block number become illegal
Because the previous block number they store now becomes illegal
So changing one block alone will jointly make all subsequent blocks The content becomes invalid.

But to prevent tampering, hashing is not enough
Because today’s computer computing speed is powerful enough and can calculate thousands of hash values ​​per second
This way You can tamper with a block and recalculate the hashes of other blocks, making your block legal again.

So in order to reduce this risk, the blockchain also uses a technology called proof of work
This is a mechanism that slows down the creation process of new blocks
In the Bitcoin area In the blockchain, it takes about 10 minutes to complete the required proof of work and add a new block to the blockchain
This mechanism makes the tampering of the blockchain more difficult
because once it is tampered Once a block is obtained, the proof of work of all subsequent blocks needs to be recalculated.

Therefore, the security of blockchain technology mainly comes from hash value and workload proof mechanism.

Blockchain also has a mechanism to protect its own security, which is distributed
Compared to using a centralized entity to manage the blockchain network, blockchain uses a peer-to-peer network, and anyone can join
When someone joins this network, he will get a copy of the entire blockchain
This person can use this to verify whether all blocks are still legal and unblocked Tampered, that is, different nodes can also verify each other.

When someone creates a new block,
the new block is sent to everyone on the network.
Everyone then verifies the block to ensure that it has not been tampered with.
If everything is verified to be correct, then everyone can add the new block to their own area. On the blockchain
We can call it that everyone on the network has reached a "consensus".

All nodes in the blockchain network reach a consensus
They agree on which blocks in the network are legal and which are illegal
Those blocks that have been tampered with will will be rejected by other users on the network
So, to successfully tamper with a blockchain, you need to tamper with all blocks on the blockchain
Recomplete the proof of work for each block and control More than 50% of the users in the blockchain network
Only in this way will the block you tamper with will be recognized by everyone
It can be said that this is basically impossible to do!

Blockchain technology itself is also constantly developing
For example, a later technological improvement is called smart contracts
Smart contracts are simple programs stored on the blockchain
br /> It can automatically execute based on the conditions recorded in the contract. As long as the conditions are met, transactions will be automatically completed in accordance with the contract
For example, automated Bitcoin transactions can be realized under specific conditions.

Learning materials:
https://www.youtube.com/watch?v=SSo_EIwHSd4